Wow! Thanks so much everyone for your advice! I'll take everything into account, and I'm going to take things really slow.
A bit about myself - I've been riding on and off for six years now, although I'd still consider myself a novice. Been working on developing a solid seat (my legs still swing occasionally) and doing a tiny bit of jumping. Would really like to go into showjumping although I don't think I'll be very competitive about it.
I used to share a TBX mare (had her two days a week for a year) so know the basics of horse care. Heidi taught me heaps but unfortunately she didn't jump. I've since ridden all sorts of horses - lazy ones that plod along, overexcitable ones that would not stop cantering, great big German warmbloods, little Welsh B ponies... I don't know what I'm looking for really - I figure I need something reasonably experienced so I can learn from him/her, but if s/he never puts a foot wrong, i.e. if there's nothing to fix I might get bored!
I have a question: do you all have insurance for your horses? If not how much money do you put aside each month in case of emergency?