Hello Paul... No worries about the response time... I hope your lady is recovered and now well?
The 7D is a good camera but I bought it for my wife new from the US and had it shipped to Calgary in Canada where I live. The US price was about half that of the Canada price so it made sense. The site I used and still do for much of my gear new and used is B&H Photo...
http://www.bhphotovideo.com/
Have a look in their used section... I found this 7D
http://www.bhphotovideo.com/c/product/80...gital.html
that is very cheap at GBP 470 at todays rate...and looking at their condition rating it's in very good condition and worth considering. There are 5D's and 40's, 50's 70D's and some 1 series there too. Have a look..?
Not sure where you are.... in UK take a look at -
http://www.lcegroup.co.uk/Secondhand-Sea...Results=12 There are quite a few 7D's for sale at the LCE. Your location may have a store and they can always get a camera from another UK store to your location for you to look at. Their price is close to the US price for the 7D so it may be cheaper to buy local without P&P and import duty? Have a look on the LCE site anyway for any other camera or make come to that. They are great people to deal with, and they are there to help you buy a camera .... not just to sell you one! You may even be able to spread payments... not sure on used though.
The camera you buy will, unless it came in with a lens, will be a body only... it will have all the leads, battery and charger though.. now you need a lens to make it work as a camera... another story! Have a look at again used...( nothing at all wrong with buying used... like you would a car... but have a good look at it or take someone with you who has knowledge) I would always say to buy the best lens you can afford... the "L" series will outlast many bodies and will give longer service than the lower spec lenses. Either way... avoid really low end lenses with plastic mounts... they wear rapidly and have a tendency to fail. As a first lens... if you can afford it the (used) ef 24-105 f4 L IS is a good all round walk about lens
http://www.lcegroup.co.uk/Used/Canon-EF-...21779.html.
If that is out of your current reach try a used 28-135 mm f3.5-5.6
http://www.lcegroup.co.uk/Secondhand-Sea...Results=12
The issue with lower end lenses is they get dust and moisture in them more readily than the "L " series which have environmental protection in the form of seals - that's part of the higher costs though. The 7D is a crop frame at a 1.6 factor so your 24-105 becomes a 38.4-168mm, the 28-135 becomes 44.8 - 216mm so both will give you a marginal reach increase but will compromise the wide angle end...
Have a look around... I would be wary of Ebay... you hear stories of good paid for and not as described or just not turning up or whatever and, of course, some great buys... Caveat emptor!
Lastly I would say READ - LOTS! :-) get to know photographers and canvas their opinions look at test sites and READ and with knowledge you are able to make an informed decision....
http://www.dpreview.com/ is a good site amongst many.
I wish you luck... let us know how you get on and what gear you do get?
Kind regards
Rolf