Hi, GEGE -
Congratulations on the new Silvia! I have read similar posts on a number of message boards in the past. The universal thread seems to be buying pre-ground coffee.
I think most folks will advise that you are going to need to buy a good burr grinder and grind for yourself, preferably immediately before load/tamp/brew.
I have a Rancilio Rocky (doserless) that I am pleased with. This is probably the "least" grinder you will be happy with. I understand there are comparable (maybe better) similar models in other brands - but I would not suggest dropping down below the level of these machines in grind uniformity and adjustability.