I'm Gareth, the generic poster, with the cliched 'oh dear, what has someone just given me?' thread.
Unfortunately, horticultural/forestry arts aren't my strong point. Snakes are. If somebody gave me a snake which I didn't know what it was, and nor did they, I'd be concerned because I wouldn't be able to provide the right environment for it in terms of temperature & humidity. It's the same with fish, and it's also similar for trees.
I don't know what it is. I also don't know how old it is. Yay for mainstream Garden centres-EDITED - PLEASE REPORT THIS POST-DIY stores selling 'Bonsai trees'. It's your typical 'gift', and your general novelty tree, which I actually find hard to define as Bonsai.
As a result of not knowing what it is, I don't know any of its requirements, and can't give it the love it needs - if it's still alive that is. So there we have it. It's going to die. [/pessimist]
It was only bought for me as the person in question saw me reading books on Bonsai:
The Bonsai Survival Manual - Colin Lewis
Bonsai from Native Trees and Shrubs - Busch
Indoor Bonsai - Paul Lesniewicz
The plan was I was going to visit a special bonsai nursery, pay for a hardy native plant or two, and use them to learn the basics on while growing some others from scratch. I believe in literature and research, and not impulse buys (or anonymous gifts

The leaves look very much like a Chinese Elm to me. Is it a Chinese Elm? There's a tag in the soil which doesn't state which tree it is, but that it has been 'imported from the far East' - or so it claims.
[url=https://img148.imageshack.us/my.php?image=73317143us8.jpg][img]https://img148.imageshack.us/img148/2382/73317143us8.th.jpg[/img][/url]
[url=https://img171.imageshack.us/my.php?image=75671116ug8.jpg][img]https://img171.imageshack.us/img171/5488/75671116ug8.th.jpg[/img][/url]
[url=https://img385.imageshack.us/my.php?image=95591798jy7.jpg][img]https://img385.imageshack.us/img385/6192/95591798jy7.th.jpg[/img][/url]
[url=https://img171.imageshack.us/my.php?image=23863986ee9.jpg][img]https://img171.imageshack.us/img171/5392/23863986ee9.th.jpg[/img][/url]
[url=https://img171.imageshack.us/my.php?image=96146139pe7.jpg][img]https://img171.imageshack.us/img171/1787/96146139pe7.th.jpg[/img][/url]