The time I stood in front of Virgin checkin moving half the contents of one bag to another because all my American grocery goods made the one bag too heavy...I will never forget my embarassment. Equally I will never forget how mundane this was for the clerk, and I realized they go through this all the time. And, as time went on, I gradually moved across to using things sold here (though there are a few I will NEVVAH give up). Mindy's right, there's great stuff here. And Jana's right, coming across with your comfort things makes the transition smoother. It's not being dumped on a totally different planet all at once.
Boots is a good site to check out; you may also look through what Tesco has to offer with their online shopping.
Since I am older and infinitely wiser...okay, I am older and like to give a lot of advice...I would suggest you come across without all those products. Get a few you can't do without until your first venture to the store, like shampoo and toothpaste. Maybe even some skin products you just can't live without. Save room in your baggage for the important, non-replaceable stuff, and then go nuts in the shops here, trying out all the new stuff. I've come across some incredibly wonderful surprises. (I have sensitive skin, for instance, and was at first nervous I'd have to live with constant rashes, until I discovered the products here are much better for my skin.)
Two things I don't use UK-style are deodorant and tampons. Everything else I prefer here. Personal choice.
As for what you listed...
Clean and Clear - Got an extensive range:
Clean & Clear Cleansing Lotion 200ml £2.39
Clean & Clear Cleansing Lotion Sensitive 200ml £2.39
Clean & Clear Cleansing Cream Washing 150ml £2.75
Clean & Clear Dual Action Moisturiser 100ml £3.45
Clean & Clear Exfoliating Daily Washing 150ml £2.49
Clean & Clear Deep Cleansing Facial Wipes 25 £2.48
Clean & Clear Fresh Foam Washing 150ml £3.39
Clean & Clear Cleansing Lotion 150ml £3.49
Secret Deodorant - I was sure I'd seen this somewhere on the shelves here, but the only things I see listed in my grocery aisle are: Mum, Sure, Dove, Nivea, Sanex, Soft & Gentle, Natrel Plus.
Biore Face Stuff - Dunno what it is, but you can bet there's something same or even better here. I use Dermologica stuff.
American shampoos - Loads of shampoos you're used to seeing down American aisles, including L'Oreal, Alberto Balsam, Organics, Dove, Neutrogena, Johnsons, Elvive, Herbal Essence, Head and Shoulders, VO5, Pantene, just to scratch the surface. You will also find the salons have the popular salon shampoos as well.
Mentadent - Yes:
Mentadent Original Toothpaste 100ml £1.00