it is impossible to enlarge a raster image (gif, jpg, etc.) without loosing quality. if it were a vector image (eps, ai, freehand?) then it is possible to scale it without the loss in quality. raster is pixel based and used to display photographic images etc. vector is all mathematical and used for line art and such. you could try to run your image through a raster to vector conversion program like Adobe streamline or Corel trace, but then you would still loose certain aspects of detail.