If you're happy to spend a bit of money and you're looking for top end designers, go to Dribbble - Show and tell for designers. Loads of large companies like Microsoft and Apple scout designers from their. It's invite only so you only get good designers and you can see all their work... Generally though, expect high prices than you would pay on oDesk / elance..
I'm seeking a front end web designer for a bootstrapped startup. I notice a good number of the 'weekend' projects posted have great web designs, how did you find your designer or did you do the design work yourself
I found my designer via a design contest that I placed on Sitepoint.
The platform is no longer on Sitepoint.
I have never looked back. Still use the same guy to this day, 4, going on 5 years down the line.
I would suggest 99designs.com
Some great talent out there.