I would say if you are planning on sewing clothes (I think decent stitch quality matters more there than other crafty things that just don't have to stand up to hard wear) to budget as much as you possibly can and then spend that money on a straightforward machine that does forward, backstitch and a zig zag. A one step buttonhole stitch is also fab (unless you rarely/never plan on making buttonholes) - the multi-step ones are a pain in the arse IMO. I make pretty much all my own and my kids' clothes and I have literally never used any of the other stitches on my machine. The only exception would be if you want to sew t-shirts etc in stretchy jersey material - then you'll need a machine that can cope with stretch fabrics (mine theoretically can, but I have a separate overlocker machine for knits).
I have a Husqvarna Viking, which I adore, but other brands I have heard great things about are Janome and, if you're seriously rich, Bernina and Singer.
If there's any chance of stretching your budget I think this Janome or possibly this Husqvarna would be pretty good. Also be aware that extra feet (most likely one you'll want is a zipper foot and possibly a buttonhole foot if your machine has the option of an automatic buttonhole) are reasonably expensive, so if you think you might need any of those, consider a package. My machine cost me something like £275, but among the extras that came with it that I use a lot are the two zipper feet (normal and invisible), teflon foot (for sewing waterproof fabric), quilting guide (v useful if you plan on quilting ever), free motion foot (ditto), 1/4" foot (ditto again), buttonhole foot and edging foot (for pintucks and edge stitching - makes clothes look more professional), which would have cost me about another £75 to buy separately.
Sorry for the essay, hope it helps a bit! I get v excited about sewing machines 