You can look on freelance websites to both find a typical rate and to post your project so others can bid. I have used ScriptLance with success. I think it's best to have a budget in mind for your entire project, and ask developers (possible candidates, at least) how much they would like for doing the work you ask. Developer input will probably be more useful on a case-by-case basis, provided you give enough information for candidates to give a meaningful quote.
answered Jun 06 '10 at 21:02