Hi mestrejorge,
With PhDs the entry requirements are usually less defined that for undergraduate degrees for example.
What this means, is that you probably need to find some PhD programmes that you are interested in and then contact the institutions to discuss your particular circumstances.
On FindAPhD.com, you can search for PhD courses by keyword, area of interest or university:
http://www.findaphd.com/search/
Each of the PhD courses that are listed on this website will show what funding if any is associated with the opportunity, the eligibility criteria and also an enquiry link to contact the university directly. This might be a good way to find some courses which you are interested in, and then you could contact the university or course provider to see whether you could undertake the PhD on a part-time basis etc.
Good luck with your search,
Jorge