Baines - I largely switched back to film recently and it's a fun and different experience. Some very good film cameras are available for fairly cheap online. You can get a rangefinder like a Canonet 17/QL17 for under $50, which isn't an SLR, but it has a nice 45mm f1.7 lens. I recently picked up a Canon AE-1 Program SLR with a cheap zoom lens for $50, which is one of the super popular film SLR's. I also got a Refelkta dual lens look-down 120 film camera with light meter, bag and a couple of old flashes for $35.
I don't know what prices are like in the UK, but 35mm runs $2-5 per roll and a similar cost for developing, leaving you at $5-10/roll. 120 film costs about the same, but you only get 12 shots instead of 36.
No, you can't scan negatives without developing them first. Do you already have a scanner that will scan negatives?
If you haven't really shot film, I recommend doing it sometime.