yeah, the only thing i can add to those is:

need a common brandname for bottled water. Over here, at least in New York, Poland Spring is the most common, but I need something thats common over in Britain.
We drink a lot of French ones (sparkling) like Perrier and Evian. Most popular British one (still) is Highland Spring.

Also, I need a brandname for a backpack; do you guys have JanSport over there?
Not heard of JanSport ....will get back to you on this
need a common brandname for bottled water. Over here, at least in New York, Poland Spring is the most common, but I need something thats common over in Britain.
it really depends on where you are. In a restaurant then it's likely you'll get some brand you've never heard of. On the go, people tend to have still water, but this differs from place to place. Buxton is a major one is the Midlands, but Evian is also pretty large.

Also, I need a brandname for a backpack; do you guys have JanSport over there?
If it's technical then North Face is very popular, though they're quite urban now. JanSport is quite rare. If you're looking for around town bags or inflight luggage, things like Gap, Karrimor, Berghaus or Eurohike are quite common and affordable bags.


~Josh