You might want to try finding a tutorial by Alex Alvarez (Intro to 3d Modeling with Maya).  He creates a Grey Alien figure that is good exposure to topology.  Especially when it comes to weight maps.

Also Alphaseed (formerly part of AerySoul) has a tutorial floating around for the details like buckles and straps.

 

I've had some success with copying the faces of where I want the laces, pasting those faces in place.  I hide the original object, leaving my partial selection.

Then I retesselate them to what I want, for example 'x' for the laces. Then select the lines going along one axis, copy, paste, the apply thickness. For the laces that will overlap, I select the lines going in the opposite direction, copy, paste, readjust the vertices so it will go over my existing laces (cylinders), than apply thickness.  Warning, you may need to be careful of what vertices you delete by reshowing the original mesh and seeing what intersects back into the model.

 

Then again you can just 'free hand' the lines then apply thickness or extrude the lines.

 

For buckles, I've made the metal portion and the part that loop through it separately , then positioned them in place where I wanted them.  Then I connect them to my clothes.

 

Hope this was useful,  good luck.