Well this looks pretty easy actually. Here's 2 video cards, each will run 3 monitors. Run one monitor off one of the 2 DVI ports, run the second monitor off the Display Port port using an active adapter like tedster said. Run your TV off either the HDMI port or the 2nd DVI port (which as we have seen above can be adapted to any output). You would be hard pressed to find a new TV without a VGA, DVI, HDMI, or even the RCA component inputs, or even all of the above. Cables are readily avail.
XFX HD-577A-ZNFC Radeon HD 5770 (Juniper XT) 1GB 128-bit GDDR5 PCI Express 2.0 x16 HDCP Ready CrossFireX: $145 (for a mere $10 difference I would definitely go with this card)
XFX HD-575X-ZNFC Radeon HD 5750 1GB 128-bit DDR5 PCI Express 2.0 x16 HDCP Ready CrossFireX Support Video Card: $135I'm not real sure what the big press is for a "TV" for the 3rd monitor. It would seem to me that 1920x1080p is going to be the same visually since they are the same resolution. Unless you are going to buy an outdated TV with an outdated resolution. The side by side for before and after comparisons. Unless you just want 3 monitors; 720p, 1080p or whatever is a standard resolution. It will look the same whether a monitor or TV. If there was a difference, you would have to have a TV with the same res as your monitors to make any true comparisons. That is unless you are talking some ginormous TV screen like 52 or more inches then you are dealing with dot pitch size/viewing distance problems (grainy picture when to close). No amount of editing can make that go away.