We also love lego! Where would we be without ti?!
My oldest is really into lego star wars at the mo, however the bigger sets are really expensive (silly me has bought him one of said sets for xmas, needless to say he aint getting much else!)
Like theoldwomanwholives in a shoe, a big general tub if you can find one is a good start, ot the Lego City sets are slightly cheaper. Hope you manage to find something.