nice, i use a 105w cfl, and standard 48" 40w tubes for veg. i'd like to find some of those high output T12s before they stop making them. all i got for bloom is a 250w hps.
I can offer some help. Fixture:
http://www.doitbest.com/Flourescent+light+fixtures-Lithonia+Lighting-model-UNS296H0120CW20GEB-doitbest-sku-543160.dib
With the fixture you will need to do some customizing. It does not come with a reflector. In my case, I just slipped a strip of mylar between the bulbs and fixture.
I have three of these light fixtures side by side about 5 or so inches between each fixture. I was able to use one piece of mylar weaved between the bulbs and fixtures and then stapled to the framework I have holding up the fixtures. This kind of gives the effect of the ceiling of the veg area being one reflector. I am sure there are better ways to do this, but it was a quick fix to get it to reflect evenly. Just a thin sheet of cardboard painted flat white slipped under all of the bulbs would probably work fine too.
The spx bulbs can get to be very expensive, like $70 each and at some places you have to purchase a case of 15! The sp bulbs are probably the best deal, those are 9,200 lumen, and the cost is about $29 each, still you have to purchase a case of 15. I have used the cool white HO lamps and they work great too.
Here is a spectrum comparison chart. You can select two bulbs and compare the spectrum wavelength.
http://www.gelighting.com/na/business_lighting/education_resources/learn_about_light/distribution_curves.htm
In my opinion the 8 foot lamps are the way to go. Much more efficient than the 4 or 6 foot.
Lamps:
http://www.grainger.com/Grainger/wwg/search.shtml?searchQuery=f96t12/sp30/ho&op=search&Ntt=f96t12/sp30/ho&N=0&sst=subset
I have not tried all of the different bulbs they offer for T12 HO. The SP and SPX are not like your typical fluorescents. I believe the government has banned them, not sure though. If so, I have no idea why because they are quite efficient. Maybe because of the chemicals inside or my best guess is that they put out UV rays. These lights are meant for shops, warehouses, offices, places where public may be. I really do not know. I sure wish I had the extra funds. I would be stocking up on all different spectrums. Worry not, the cool whites work great and are the least expensive. Just have to be sure to get the 110 Watt lamps, not the 95 watt ones.
The T12 HO 8 foot bulbs are my favorite fluorescents.
Hope this info helps. I am not claiming that they are better than MH for veg. I just think they are best fluorescents. The fixture can easily be mounted in a flower area for additional lighting should the need arise. You can even mount them on a wall to add light to the lower parts of the plants.