There are not many current makers - Kyosho of Japan is one (hard to find, expensive, mostly Ferraris), and there are some racing cars in the Hot Wheels range such as the Ferrari P4 and 512M and Chaparrals 2D and 2F; also Siku of Germany do a few, and Tomica - but there used to be lots of nice little cars available, such as most of the 1974 and 1982 F1 fields from Polistil, which can be picked up quite cheaply at collectors' fairs.
This site specialises in 1/64, and lots of good stuff can be found by searching (takes a while as it's a big site) :
http://www.breithaupts.com/toycar.html
For Matchbox:
http://www.mboxcommu...tchboxlinks.htm
(those lovely Ford GT40s and Lotus 25s...........)
Here are my Wheels Chaparrals, as bought:

Paul M