Surfing Waves

Hi. I live in upper Michigan on the shore of Lake Superior (we get big, choppy waves here every so often). I started surfing two summers ago while I was lifeguarding by using the rescue board...it is really long and it's not very orthodox, therefore I am shopping around for a long board on ebay. My question is this: as a beginner surfer, what qualities should i be looking for in a board? Are there "surfboards" on ebay that i should be avoiding at all costs (Wal-Mart-like brands that no right-minded surfer would EVER recommend)?
I cant really go to a surf shop cuz the nearest one is like 900 miles away, and i dont plan on spending over $800. Also, for all you pro's out there who only insist on the latest-and-greatest gear, realize that I am new to this, I dont get to go out all that much, and I will probably still suck even if i could afford a primo ride. Just need something that will get the job done. Thanks, eh.

Alas, i forgot to mention. I am 6'3" and weigh 200 pounds. Thanx.

Not really....I personally would avoid those plastic boards

You surf in Lake Superior? how often is it rideable?

you should get a BIC board as they are super boyant and more importantly, practically industructable. also they are by far the easiest things to learn on, thats what i started out with. and if you don't think you'll be out in the water enough to improve quickly, then they are probably the best option for you. sorry i can't tell you what size you'll need, i'm a bit hazy on stuff like that. I'm 172cm and have a 7/6 by 20 1/2 by 2 3/4 mini mal . otherwise get a nice mini mal with a bit of rocker in it - makes it go faster , is easier to paddle and balance on and is a good all round board for when you make progress. whatever you get you should be able to resell it anyway as long as you look after it.

its the newbie here...thanks for the info. Superior is rideable usually a few times a month in the summer and more-so in the fall. Definately not like ocean waves, but its still fun.

seeing as you plan on surfing on a lake, you should probably get the biggest most boyant board possible, as that way you will be able to catch much smaller waves as well as the bigger ones, thus maximising your time spent in the water having fun. sounds pretty crazy though, i didn't know you could surf lakes!

yeah, surfing on a giant lake is much diff than ocean waves. not nearly as consistant, choppy as hell, and they break really close to shore. but lake Superior is a huge-ass lake and the wind kicks out some rideable waves once in awhile (the biggest i've surfed here were like 6 or 7'). like i said, i learned on a 12' lifeguard rescue board, so i'm thinking about buying a 9' or larger. thanks to all who responded.