I've been where you are so I can relate.
I strongly recommend Motley Fool (as previously mentioned) and Buy and Hold (as also mentioned).
I got my first IRA from Buy & Hold on 4/15 (Roth for yr 2000). I have few, if any, complaints about their site. Their online support was pretty fast to answer my questions. I haven't called them for anything so far.
My only complaint was that I think they should offer their $9.99/ month unlimited trades for IRAs too. Otherwise, it's a good system. The trades are among the cheapest. You have to pick out your own stocks (I don't think that's a bad thing) which may be a bit overwhelming. There are SO many choices. It helps if you have some idea what you want to invest in before you start "shopping".
You asked about low minimums. If you sign up w/ the EZ Vest feature, the trades are a $20 minimum-- done monthly, quarterly, etc-- your choice. The prices for EZ Vest are $2.99 for the 1st trade, $1.99 for others.
I plan to set up my 2001 IRA there too, so I am pretty satisfied w/ them.
OH! I almost forgot! My one regret is that I forgot to go there thru MyPoints to get my 1,000 points! (I'm going thru MyPoints for my 2001 IRA for sure.) Got to get those points.
It asks you if you have a code or something, so there may be other deals out there. I didn't know of any. (They didn't mean the MyPoints stuff.)
Hope that helps!
Good Luck!
Q
PS I had thought about using ShareBuilder, but their trade prices recently jumped -- as in doubled, I think!