Lance - Got my new one from here and it's identical to the one I originally paid £45 for:

http://www.i6automotive.co.uk/snow-foam-lances/

As for foam, you can't go wrong with Magifoam - one of the originals:

http://www.autobritedirect.co.uk/ind.../magifoam.html

I've moved on to Auto Finesse Avalanche at the mo which isn't quite as "clingy" but seems to do a good job:

http://shop.autofinesse.co.uk/avalanche-1litre

Add a little citrus power (also Auto Finesse) to pep it up a bit or simply add citrus power to the car 3 minutes before snow foaming it for maximum cleaning power.

Wheel cleaner - we use Bilberry of varying dilution rates depending how bad they are:

http://www.cleanyourcar.co.uk/valet-.../prod_499.html

Lumps on the wheels may be tar - so either use some tar remover (Tardis for instance) or get a bit of used clay and clay it off.

EDIT: if you can't be bothered to get all the snow foam stuff out, then just applying Auto Finesse Citrus Power is a good pre wash step: