So with the errata adding in extended tests to learn skills and the now extreme usefulness of instuctors and Tutorsofts, do you think that it is possible to get a tutorsoft for skill Groups?

The book only gives a flat price of rating x 500 for tutorsofts, so if you think that it is feasible for a skill group tutorsoft what do you think the cost should be?

Base x 2.5, just like the karma difference and BP difference between skills and groups.
So rating x 1250Y.
Or, just make them buy all the tutorsofts in the group. Depends on how much emphasis you want on virtual training vs finding instructors.
Consider limiting skill group tutorsofts to rating 4, and if they want the really highly rated ones they have to buy them all individually at full price.

Is this worthy of a houserule? I´d just make them buy all individual softs. Package deals are not tied to this occasion, and I´m not making up rules for those.

I will say, I do not plan to use what I suggested above. But if someone did desire discounted group tutorsofts in their game, that's the price I would suggest.