
Alton towers do have lockers, and the shelves as already pointed out, although leaving your valuables on the side of a ride is not secure so be careful, try not to take to much stuff with you.
As for photo's you can buy a ticket although off hand I can't remember the price, with this when you go on rides that take pictures you buy the photo and pick it up later when you leave the park near the exit. (not to sure if it's four or six photo's) It's a good option and we allways buy it. Most of the major rides have camera's and they photo's are pretty good, just remember to pose LOL :-D
Another thing is to wear comfy shoes, because you'll be doing lots of walking although there are sky lifts they only stop at three places.
Try not to wear jeans as they take ages to dry! They do also have huge dryers but they are quite expensive and I don't know how effective they are getting you dry.
Yes sometimes the queueing is bad, but if you can try to go during the week and not to late in July as lot's of schools have trips there, I no it's late now but we allways try to go late March, during May (but not during holidays), and early June.
Food is average priced and there are some nice places to eat, there are the fast food options too.
Have fun! It's a super day out and we love it there. :-D
Diane