Have you been to a local garden center just to look around and see what is available? There are tons of products/brands out there and I can't assume what is available to me is also available to you.
If you're looking for decent ready-made mix, go through the selection and check the ingredients\derived from list. Anything with urea or polymer-coated anything is out. Anything that says "time released plant food" or "feeds for x months" is out. If you can actually see the product and grab a handful of it, note the texture (it should be relatively light and airy). Anything with copious amounts of twigs, bark, wood chips is out. Same goes for perlite. Some perlite is acceptable but you don't want a mix with a shit load (it's counter-productive in terms of cation exchange/nutrient availability).
If you can give a selection of brands and their ingredients here it'll help us help you.
Otherwise, if you can get raw materials and want to mix your own soil, check out what you can get for compost. A lot of the stuff they sell as 'compost' at hardware stores around here (in the US) is really crappy for container gardening. It's often more like heavy top-soil and full of rocks and other undesirables. I use BioMax compost for my indoor containers and often screen it before using to yield an end product with a fluffier texture.
