I am relatively new to Linux (2-3 months) and am looking at buying a new desktop. I know Walmart is now selling computers with Lindows (sorry Linspire) on them but I am more interested in continuing to use Fedora. I don't want to buy a new system if it means I can't use Linux with it.
When I first got my current system (several years ago) I wanted to get into Linux but the compatibility wasn't there. I don't want to go through that again.

Does anyone have opinions on which retailers (gateway,dell, etc.) sell desktops that are most compatible with Linux?
Would it be easier for me to go to a small computer shop and ask them to custom build a system with only Linux compatible hardware?
Are there any reputable websites that sell Linux systems?

Thanks in advance for any opinions.

why not build your own? you can get everything you need at sites like newegg, mwave, etc. then you know exactly what's going into it, and you can make sure all your components are linux-friendly. (it's also fun. )