You do really need to go to a shop to try a camera.
Jessops will probably have a store near you and will have the latest Canon DSLRs in for you to try.
A Canon 600D is good, but it's the current model so will be more expensive.
Canon model numbers are easy to understand:
1100D and 1000D are the budget models.
400, 500, 600D are mid range.
450, 550, 650D are slightly higher
40D, 50D, 60D are high mid range/almost semi pro.
7D - semi pro/low pro model
6D - brand new full frame but small Pro model
5D (Mk3 is current model) is the pro standard.
1D/1DS/1DX - top of the range Pro models.
If the number (of the mid range) model starts with a 4, it's older, it it starts with a 5 it's about 2yrs old, if it starts with a 6, it's the current model.
So a 600D is the current model in the mid range. The 400 is the older equivalent (Horney has one) but it's still decent, although it doesn't do video. Most of the newer models will do video.
Looking at DPReview.com is good for gauging specs, but you really need to feel what they're like in your hand and try out things like the menus and changing modes, etc.
Here's a spec comparison for a 600D, 550D and the 1100D:
http://www.dpreview.com/products/compare/side-by-side?products=canon_eos600d&products=canon_eos550d&products=canon_eos1100d&sortDir=ascending