Thanks for the welcome. Yes, I am the fellow with lots of plants pictured on mammillarias.net. Those pictures were taken some years ago - about 5 years if memory serves - so most of them are somewhat larger. And a few of them are no longer with us; having suffered at my hands they passed on.
I currently am a member of the Tucson Cactus and Succulent Society, - another site where I've posted some pictures. If you haven't checked out our web site, give it a try. (Please google Tucson Cactus and Succulent Society, as I'm not sure how to enter web addresses yet) We have over 1000 members, with around 300 of those being active in such things as cactus rescues, workshops, conventions, and such. But there are only a very few of us who specialize in particular genera...I can only think of 3 others who are ardent Mam collectors.
Living in Arizona certainly gives one an advantage as a grower. Until eight years ago, I lived on the extreme north coast of California - think redwood trees, fog, rain, and top temps being 70F. A friend from Ireland said that it reminded him of areas of Scotland! I mostly grew Lithops and other Mesembs in greenhouses, as Mams were very subject to that orange rot. But my first Mams were purchased when I was a lad of about 12, so there has been lots of time to kill/grow my share of plants.
Well, enough about me...if you have any questions, please ask!