sadly, I do not have "pervyi Yak" so I cannot comment on the quality of the drawings. (Kuznetzov)
it is on my list of books to get.
Chris Banyai-Riepl's drawings of the Yak-9 (side views) do not look right to me.
(his line drawings are in the previously mentioned "Soviet Airforce Fighter Colours 1941-1945")
his artwork for the Yak-7-37 is totally wrong as it depicts the cockpit in the standard location, not moved back 400 MM as on the Yak-9T.K.DD and M.
this aft-positioned cockpit was neccesitated by the MPSH 37 MM cannon.
those websites you mention are only re-using the drawings from Modelist-Konstructor (Russian model builder's magazine)
http://mkmagazine.almanacwhf.ru is part of the URL (full one eludes my memory at the moment)
you may want to check out Alexei Matvienko's work here:
http://www.sovietwarplanes.com/mig3/...-matvienko.htm
(translated by Alex Ruchkovsky)
he has more sources than I do and will tell you what parts of which drawings are correct and what is not.
P.F.
p.s. personally I would like to see a sample of the drawings from Pervyi Yak (the first Yak)
good drawings for the Yak-1 and Yak-1b are hard to find.