As for GPUs though, dolphin really doesn't need an uber graphics card. But since you mentioned pc gaming, we might as well ignore that.
Seeing that you're getting a core i7 and wanted to get a GTX295, I'd say you don't have money issues. Personally, I'd go with the GTX285 instead since it's currently the fastest single GPU.
If you REALLY wanted SLI in the future, you could just throw in another 285 since money seems to not be a problem. It should then match or even beat the 295. (this is assuming you get a motherboard supporting SLI though)
Only problem is that AMD/ATI will be launching the Radeon 4890 supposedly on April 6, and we don't know how it'll stack up to Nvidia. Currently the 4870 1GB can match the GTX 260. I'd hold off a bit until it launches, and if it performs better, go with a 4890 instead. Then like the 285, you could throw in another for crossfire in the future.
If you need enthusiast PC hardware advice, I recommend the forum
Overclock.net - Overclocking.net
Also recommend
[H]ard|OCP - hardocp.com for enthusiast PC hardware reviews.
And for where to buy, I recommend
Newegg.com for PC parts and
MonoPrice.com for connectors and cables.