> sanitizing corks?
I keep them stored in a sealable cooler with some metabisulfite dissolved in water. It produces a gas chamber that keeps the corks sanitized and moisturized.
> types of corks
At a minimum, use #9 corks (not #8). Other than that, the more expensive, the longer they last.
> recommendation for a corker?
Portuguese is the cheapest with a plastic head (part that compresses the cork)
Italian is better with a brass head
I use a Swiss corker (lot more expensive, but I found one off craigslist).
If you can test one out, do so. They are different heights, so that may be a factor for you.
With synthetic corks, the Italian is supposed to be a little better.
There are different levels of the Portuguese. I think Red model and Blue Model. The Blue is better.
Check prices on Craigslist, and look for a deal. $45 for a red Portuguese. $60 for a Blue, and $85 for an Italian.
The Italian has attachments you can buy for Champagne, and Beer.