Are you wanting to brew from syrup style kits, or were you wanting to brew all grain? Asuming kits as this is the kits thread, a basic plastic fermenting bin and bubbler air-lock is a good starting point, and will probably set you back around about £10-15ish. Were you wanting to bottle your beers, or were you wanting to put it in a keg to serve? A basic pressure barrel and tap is probably around £25ish, and is a great easy starting point. Bottling can make it much easier to put a couple of botles in the fridge as and when wanted, but can be a little bit more fiddley. You will probably want some sort of tubing to syphon the beer from your fermenting bin into bottles or a keg. A paddle to airate the wort to help the yeast get to a good start is probably a good idea too.
Sanitiser. Lots and lots of sanitiser. We used VWP and StarSan, but I think StarSan is currently harder to get in Europe (if Cornwall hasn't gone independant yet), but other similar things seem to be sold in the usual suppliers too. If you're doing lots of kits, a second (supermarket value) kettle might come in handy, as plenty of hot or boiled water is usually pretty handy to have around.
Other sundry bits of gear would be things like a small tub of petroleum jelly for sealing screw threads and o-rings. A hydrometer for checking fermentation has finished. If you are putting your beer in a pressure barrel, some allow you to increase the pressure in the barrel using a CO2 charger, like a soda-stream.
A bottle of supermarket thin bleach (diluted with hot water) can help to clean all kit for it's next use. Campden tablets to remove chlorine and chlorine related chemicales from tap water might not hurt too.
On the other hand if you are wanting to go all grain, then get yourself down to St Austell for their tour and let them know you're an all grain home brewer. Take a couple of new clean thermos flasks and they will usually be happy to fill them with their own yeast for you.
We did that on holliday, brough the yeast home and made a lovely smoked tea and orange pale ale using it (inspired/blatently stolen the idea from Theakstons "Rivers Answer", that they don't even seem to say ever existed any longer).
But mainly just have fun.
This thread used to be much more lively, but I still think people will be very happy to answer any questions you have.
Rapid bubbling is a good thing, it should calm down in a few days. If the krausen gets too high and you have a bit of tubing then make a blow off tube. 18-20c is perfect if you can hold it there.