A Local LFS was shutting down so I got a 56 Litre tank, a cabinet / stand, gravel, pump, light (hooded tank), 4 nice round stones, food, anti-chlorine, bacteria helper solution, and a little plastic plant.£100
you can get a nice 60 - 80 litre tank for about £60 with built in filter and lights.
then you will need a heater 100watts. around 10-15 pounds
then you will need dechlorinator. and concentrated amonia. for a fish less cycle or you can do a fish in cycle. about £5 for both#
tub of high quality tropical flake. buy a small pot for begging as they may not take the food meaning you have to buy more and less is wasted. and a blister of bloodworms is good.
then you will need about 12kg of substrate depending on the aquarium. if its some thing with a 60cm by 30cm then you will need 12kg enough for a covering of 5cm. i always use roman gravel which is £1.25 a kilo.
and for fish a few hardy beginners fish could be zebra danios, white cloud mountain minnows(my favourite(there a tight shoaler)), there about £1 each
and you need about 6 to start with.
and a selection of fake or real plants are good. some hardier plants first. and maybe a few ornaments or rocks. (not essential but always good)
so i would say around £100-£120 pounds to get you started. and then a few pounds a month for maintance
hope this helps. and if there is anything ive forgotten im sure other members will add to this list
They become quite addictive.
Pets@Home have a 60ltr tank with 100w heater and filter for £79 (thats if you are in the UK)