At this point, I have an idea about where other poser files belong but I'm not sure about .obj files. I thought they belonged in the Geometries folder but I searched and cannot find a folder with that name. I need to know what folder I should put them in and what are they for. How can I make use of .obj files in Poser? 

There is a folder "Runtime/Geometries" that is for .obj file that are referenced from cr2 and pp2 files.

OBJ's are not used directly, they are referenced in the same manner as actual texture maps.  You do not apply them from the library folder.

You can import an object file and make it into a prop by adding to prop library

You can make it into a figure with some effort.  There are tutorials available for both actions

http://en.wikipedia.org/wiki/Wavefront_.obj_file

It's the preferred file format for object meshes in Poser...

Sometimes you'll find downloads for props that include the object files. Many times these are outside of the standard Poser geometries folder (if the poser folder structure is used at all), usually these are included for use in other applications.

One way you can find out where it is supposed to go is to take a look at the cr2 or pp2 file (usually the cr2 since, as mentioned, the pp2 prop files don't need the objs to work - they're included to use in other applications.

A cr2 can be opened in any text editor and it will indicate where the obj and texture files go.  If you want to change the location of those files, you need to edit the cr2 file.

@ aproctor: The advice is very good, however that was not the question the OP was proposing.  By the intent of the query, the OP wants to place an .obj file in an appropriate folder for access.  It sounds to me that the OP has just a mesh in .obj format. 

Unfortunately, there is no further information about it's relationship to Poser or whether there is a .cr2 file associated with it.  Giving more in terms of a solution, at this point, may prove confusing.

(1) import from file menu

(2) Add to library (use "+" sign) with name of choice

You can use prop in scene the usual way.  In this case, the object geometry is included in prop and not external

I guess I was interpreting the question differently than you are. The OP is the only one who can tell us exactly what they were asking but they did ask this

" I thought they belonged in the Geometries folder but I searched and cannot find a folder with that name. I need to know what folder I should put them in"

My response was telling them how to know what folder you should put them in - assuming they have a cr2.  You're right - the initial question left out some information that makes it so that any of the replies may be helpful or not helpful -too little or too much information, so I don't quite understand why you singled out my response and felt it important to tell me that MY response MAY be confusing.

Respectfully, perhaps we should allow the OP to tell me if this information is useful or not, confusing or not?

Quote - @ aproctor: The advice is very good, however that was not the question the OP was proposing.  By the intent of the query, the OP wants to place an .obj file in an appropriate folder for access.  It sounds to me that the OP has just a mesh in .obj format. 

Unfortunately, there is no further information about it's relationship to Poser or whether there is a .cr2 file associated with it.  Giving more in terms of a solution, at this point, may prove confusing.

Don't mean to step on toes given the nature that the OP is a newbie and too much info can cause more confusion than help.  But you are right, let's allow the OP determine the usefulness of your response.

Thanks :)  I definitely don't want to cause confusion, but I DID think I was answering the question asked and only adding the tiny bit of info that you can change the place the geometry and texture folders are ;)

If the obj is part of a figure or prop then it will be either in runtime/geometries/vendor/product where vendor is the vendor name and product is the product name.  Sometines vendors put the obj in the same folder as the figure or prop. ContentParadise is know for that. 

Poser tends to embed the geometry file in a prop if you import an obj and then save it as a prop. You can extract the obj from the prop with Geomstripper (freesruff) but its not required.

I appreciate all of your responses. They provide useful information. I'm not yet familiar with many poser terms, so I can't pick things up just by reading, but I will learn better once I try them out.

What version of Poser are U using?

As Poser has installed a very good pdf manual in your Poser folder.

There is even a special chapter on obj files.

Quote - What version of Poser are U using?

As Poser has installed a very good pdf manual in your Poser folder.

There is even a special chapter on obj files.

I am using Poser 8. I want to look at the manual but right now I have no time. I am trying to find less time consuming answers.

The less time consuming answers may not be the most complete.  You claim not to have time to read the manual, however you are posting questions to which the answers can be found in the manual with thorough explanation.  And in the time that forum participants respond to your question, you would have found your answer in the text.  I would recommend reading the manual along side the open Poser app to truly familiarize yourself with the program.  Then post a question in the forum if you do not comprehend a specific feature. 

Being spoon fed tidbits of information from different sources will only lead to more confusion and frustration.

Quote - The less time consuming answers may not be the most complete.  You claim not to have time to read the manual, however you are posting questions to which the answers can be found in the manual with thorough explanation.  And in the time that forum participants respond to your question, you would have found your answer in the text.  I would recommend reading the manual along side the open Poser app to truly familiarize yourself with the program.  Then post a question in the forum if you do not comprehend a specific feature. 

Being spoon fed tidbits of information from different sources will only lead to more confusion and frustration.

Do you have any suggestions on how I can get to the parts that I am looking for in the manual, rather than going through the whole thing?

The individual chapters at the beginning and the index at the end of the manual.

In all sincerity if you post precise questions, people will try and give sincere precise answers, however as we have seen from the posts above, people are trying to help without the specifics of what your specific question is and as such speculation creeps in that can cloud the answer.......

edit, cross post with Hborre

here is a screen shot of the runtime, and the libraries folders fyi