I'm not sure if you mean Encapsulated Postscript
images (.eps) or generally Postscript
(.ps). In the first case, the well-known Gimp
should be enough; it can export to postscript, among many other formats.
If you want something more general, I would suggest LyX
. LyX is actually a "what-you-see-is-what-you-mean" document processor; you can call it a front-end to LaTeX, if you wish (but it's more than that.) In any case, it is a convenient way to write documents in a friendly way (including embedded figures, tables, algorithms, etc) and can export to postscript directly. Given what you said, I believe this is what you are looking for, and it is available in basically any Linux distribution out there. The downside (if any) is that, in order to use LyX, you will have to install LaTeX as well, which is a large package.
There might be other solutions as well, such as "printing" to postscript as business_kid mentioned.