There are companies that sell kits where you collect a blood sample at home, and then mail it in for analysis (except in NY, which apparently bans medical tests by mail).

Two examples:

http://www.zrtlab.com/vitamindcouncil/

http://www.amazon.com/gp/product/B004BYURTU/ref=as_li_ss_tl?...

Not aware of the actual analysis equipment being available in a consumer-level product, though.