Best site for finding good web programmers?

I'd like to build a 'smallish' web app on probably a LAMP stack (I know some PHP but not a lot - and it would also be easy to host). I know basically what's required from this app in terms of functionality and layout. I think it would take 40-80 man hours - basically a mashup of some social bookmarking sites to create a presentation of data.

Below are sites that offer programmers; any tips, suggestions or referrals for partners or contractors, please?

http://www.elance.com/p/websites/index.html

http://www.guru.com/category.cfm/100

http://www.professionalontheweb.com/

http://www.getacoder.com/projects/web_design_development_42....

http://www.vendorseek.com/website_design_services.asp

http://odesk.com/ (generally requires ongoing management by client)