Yup, no problem, I have around 90 species of rarer livebearers.
Some are suitable for a communal tank, but if you are going to breed them then you really need a species tank. I work on the basis that you need one species tank per species plus 1 growing on tank per species. As with all families of fish, some species are aggressive, some are not. Some are tiny (2cm) some are large (25-30cm); It really depends on what species you want to keep.
If you are starting out, I would start with some of the easier fish which can be flock bred and then move upwards depending upon what species you really want to keep. Fish such as Phalloceros caudimaculatus or Poecilipsis gracilis would be a good bet or some of the limias if you don't mind keeping them warm.
You could also try some of the rare species of the common fish such as the easier Xiphophorus's (platies and swords) such as nezahualcoyotl and pygmaeus or xiphidium or the mollies and guppies (Poecilia) sphenops, caucana or chica for instance would be good bets.
If you are looking for books, the best is the Aqualog Livebearers and Halfbeaks with pictures of virtually every species, although it is quite expensive; there is also a book by John Dawes which is good for beginners.
As for getting hold of species; join www.livingfish.co.uk which is free and join the BLA at www.britishlivebearerassociation.co.uk; the latter run a convention and auction in October and an auction in March when you can get hold of many of the different species of fish.
You are based in Middlesborough.
Join www.livingfish.co.uk and you may well get an invite to one of the best breeders in the country who lives near you.
