i second that. i use a pre-made glass versatop on my 20 long planted tank that i made the gutter for, they do run a few dollars though. the plexiglass can be a pain to cut but with the right tools, can look fantastic. if you can spring for the extra money for the versa top (im guessing around 30 USD for your size tank) go for it to save you some work.
on top of angels list dont forget to get end caps for the gutter you buy. at home depot i bought a preassembled wire with a plug for like 6 bucks, a switch for another 4 bucks (single pole single throw push button on/off), and a 4 pack of 18w natural daylight bulbs. what socket arrangement you want to use depends on what they have available. I just sprang for ceramic sockets I had laying around. really if you can, make it easy on yourself. the parts are out there :)