Subscribing to nursing journals is an excellent way to read articles then complete self-study tests for CEU credit. I subscribe to Nursing Magazine which keeps me updated on trends in nursing or refreshes my memory on certain areas that I don't use frequently. Attending local seminars is another way to obtain credit.

Some states do not require CEUs for nurses. For example, Colorado, Washington State, and Georgia do not require them, to name a few.
Nurses should take it upon themselves to keep current in their knowledge and skills, not only for their professional and career development, but for their own personal development as well.
Not to advertise, but I develop courses for continuing education, and in order to provide quality and relevant programs, I offer them free for nurses to evaluate. User feedback, comments and suggestions help guide me in improving my services.
Some employers have educational benefits that include discounted rates or free (not too many offer free CE classes anymore) classes. A lot of online courses out there that you can choose from, and usually accreditation by one state is accepted in other states, so check first with your state board of nursing if you are using contact hours for relicensure.