Other than Alex Teixeira, my big immediate signings were Zakaria Labyad, Yaya Sanogo, Daniele Rugani and Zeli Ismail. They went into the youth program to get some experience and confidence while adapting to Italy. Some pickups were for later, such as Tomas Kalas, Leo, Adryan and Serge Henry.
Tried to get either Eden Hazard or Jesus Navas in the 2012 summer window, but were too expensive. (Santos wanted $148 million for Neymar, about three times my transfer budget.) Ended up going with Diego Perotti of Sevilla, who fills a more cultured role on the wing. Also, I made sure to secure Crisetig and bought back the other half of Viviano (Julio Cesar is just too brittle, released both of the other backups and the youngsters aren't ready to step up well enough that I would rely on them in a major injury crisis) as well.
Summer friendlies 2012 were so-so, but beat PSG to win the Super Cup, 5-0, which surprised me. Should be an interesting Serie A season. I'm going to continue to find good young players to complement the youth side and keep the best. The idea is that the great youngsters come up together, keep the team younger (and hopefully less injury-prone) and add to the trophy case.
As far as tactics go, I've been using JP Woody and Goals Galore along with the standard 4-1-2-1-2 (which I find to be a little too narrow).
This has been one of my favorite seasons to date and I've played FM long enough to have managed Castel di Sangro, Arezzo, Taranto, Burghausen, Bayern, Braintree, Hereford, Santos, Juventus, USA and Ghana among others in different seasons.
I hope you have as much enjoyment with your Inter game as I've had with mine!