The end caps were in the same section as the other parts. I believe they may be called plugs. I found the T then found the "plugs" that would fit snuggly inside. I got the parts from Lowes, but any big-box home store should have the parts. The exhaust fan is a 4 inch 100 CFM fan I got from...
From what I've been told, you can germinate with just about any bulb. 6500k lights for veg, and 2700k bulbs for flower.
You can find all sorts of different splitters/adapters on Amazon and Ebay. I am using some of these and some of these.
3" PVC cleanout tee. $4
Screw cap. $3
End plugs. $2
Aquarium filter carbon. $5 for 3 pounds.
Drilled holes in the end plugs. Scotch Brite pads used as "pre-filter". End plugs fit snugly inside ends of cleanout tee. Will use a small stainless screw to hold end caps in. 4" dryer...