I highly recommend the Reptisun fluorescent bulbs, but they do not offer an 8.0. Only 10.0 or 5.0, and for the depth of your cage I'd suggest the 10.0's. The link below was used to show you the 10.0 bulb package, and may be able to be found cheaper elsewhere. http://www.reptiledirect.com/index.asp?PageAction=VIEWPROD&ProdID=944
For these reptisun fluorescent bulbs you will need a fluorescent fixture. Make sure the fixture holds t12 size bulbs as that's the size of the larger 2ft and longer reptisun bulbs. I suggest purchasing the fixture at a Lowes or Home Depot as they will be LOADS cheaper then a fixture you'd get at pet stores designed for fish tanks. You want this fluorescent bulb to run over the basking spot mainly, so get a fixture that is at least 3/4 to the full length of the cage. Dragons are sun loving reptiles so the more light the better. I actually use the dual fixtures on my cages.
copy and paste link to see fixtures http://www.lowes.com/lowes/lkn?action=productDetail&productId=133982-57299-8055SS&lpage=none
The only bulb that MUST be reptile specific is the uvb producing bulb which is your reptisun 10.0. The incandescent bulbs with reptile on the cover provide the same light a regular light bulb would provide, so need to paying a markup, and more money for the reptile on the packaging. To provide heat you can use any incandescent/halogen bulb that provides you the proper basking site temp, and cage gradient. Each cage is different, and to say yeah a 75 watt will work cannot be done. You need to try a few different wattages or raising/lowering your basking spot to achieve a proper basking spot of 105-115 surface temp. Whatever provides those basking temps is the wattage you need for your cage. I suggest purchasing a cheap indoor/outdoor thermometer with a probe, and attaching the probe right to the basking spot under your heat light. This will get you the surface temp of the basking spot surface. the dial thermometers or stick ons are highly inaccurate, and will give you ambient temps instead of surface. link below will show the digital thermometer with the probe. The site I linked to is actually the cheapest I have found, but for convenience they can be purchased at wal-mart, lowes, homedepot etc. http://www.reptiledirect.com/index.asp?PageAction=VIEWPROD&ProdID=1036
hope this post helps you out some. Good luck with your new dragon. As long as temps, and proper lighting is supplied you'll be off to a great start with a new dragon. When temps and lighting are correct the dragons body can then work at it's optimum, and hunger and appetite come next.