I just ordered a Mr. Aqua tank off of marinedepot.com that might interest you. They are about $50 and you can grab a bag of Eco Complete at the same time for about another $20.
The lighting isn't cheap though. That is where a lot of the financial pain comes from for me. You could be looking at about another $70 for the light fixture.
I suggest a tank, Eco Complete gravel, a small nano sized filter, a hang on back light fixture, and that will take a lot of your budget. You can do DIY CO2 which will work fine for a tank that small. Since you are trying to keep your cost down, I suggest going to a local stream or lake and gathering some driftwood and rocks for decorations. Purchasing them can be outrageously expensive when you consider they are just wood and rocks.
After that you are on your way. Stock heavily with plants and lightly with fish and then it's all about fiddling with the aquascape.
Oh, lastly get yourself some trace ferts. You can order them in powder form for the best price. I personally only add trace to my nanos and I never have problems with algae, but don't only take my advice. The official fert routine includes nitrate, potassium, trace, and phosphorous. They are all very cheap in powder form and with a nano they will last forever. Do some research on how to dose before getting into ferts because you can quickly kill off your tank or suffer algae explosions if your dosing gets out of whack.
Two 1 GA desktops, a 5 gallon, a 2.5 gallon, a 10 gallon, a 20 gallon, a 25 gallon, and two 75 gallon tanks, all planted.
I am an expert on algae, so ask me if you have questions. I know how to grow it, just not how to get rid of it.