Well I've finally found some details of the Takara range, it seems it was only available from 2001 till 2003 (i.e. the point Takara merged with Tomy), but it was quite a large range. The link below is to a site that is natively in Japanese, but thanks to the power of the web can be translated (mostly) as this link shows. Follow the links down the page a bit and there are listings of the entire range along with images of some of the trains and scenery pieces 
Takara Pocket Trains
Takara Pocket Trains
Happily collecting things all my life... 