How can I get or apply for my husband's green card if I don't have work at the moment?

Significantly more information is needed in order to provide a legal analysis. Generally, however, if you are a U.S. citizen and your husband entered the U.S. lawfully and with inspection, then you and he may succeed in a marriage-based adjustment of status application process notwithstanding that you are unemployed (and notwithstanding that your husband may have overstayed his initial visa and/or may have worked without authorization). If you do not have sufficient documentable income to meet the legal requirements, then it may be necessary to have a joint sponsor in the application process. Generally any U.S. citizen or Permanent Resident who has sufficient documentable income and who is willing to assume the responsibilities specified in the Affidavit of Support may serve as a joint sponsor. There really is no substitute for you and your fiance to consult with an immigration attorney who, after learning all of the relevant information, could advise about eligibilities, options and strategies to attain your goals, and who then could offer legal representation in the often complex application process.