This Claremont page is a little funny in that it stresses a number of foreign characters like c,q,ž,š,w,x,y,z,f that are used in foreign words only and hence their pronunciation may sometimes vary. Also, I'm not sure if anybody can get a correct idea of the 'õ' sound based on the explanation given (e in 'get'). I have always had an impression that something like o in 'row' or 'show' could be a better parallel, although this is probably also not entirely correct.
The BBC website has good pronunciations (apparently read by a native speaker), so you can rely on it. As to 'yes', as described here earlier, both 'jah' (short and 'h'-terminated) and 'jaa' (long 'a', no termination) are acceptable in the spoken language, and you can also hear many versions in between. There may be certain contextual differences as to when to prefer one over the other, but these are rather hard to define. In the written language, be sure not to use 'ja' which strictly only means 'and'. For some reason many Estonians often make that mistake, be better than that. Generally, stick with 'jah' in both cases and you'll be fine.
. Thank you!
