I'm afraid if you want a decent plate, then you have to pay the price.
There are loads of ones where people try and use 13 as a B, 4's as A's etc - but they all look terrible and are illegal. You can get thousands of these on eBay! A good old date / initials ie '11 XX' will cost you the guts of £5-7k and if you want it round the other way ie 'XX 11' its more likely to be £10-13k (obviously price dependant on numbers and letters).
Number plates seem to be a love 'em or hate 'em thing. They're handy for hiding the age of your car should you desire... and it makes it easy to remember your cars number plate if you've always got the same one!!
The best thing about them though is that if you buy a decent one, it will only increase in value.