There are no easy answers and its really yourself who needs to decide whats the best course of action. What do you want to be working at in 5-10 years time or 20 years time and then work out how to get there....
If you are going to start learning a database I would recommend Oracle as the salaries are high for people with these skills, but you wont just get the skills by reading or learning it yourself. You need hands on work.
You already have 5 years experience so dont feel like you cant apply for roles looking for 2-5 years experience. You may have to take a salary less than the going rate to get started and get experience but after 1-2 years you will then be in a position to achieve market salaries. Many companies are swayed by the candidates enthusiasm and personality as they are with their skills on their CV's so dont be disheartened with this lack of experience, experience can be gained and the good companies realise this.
Are you interested in working as an ASP.Net programmer with some SQL database experience? Or are you not sure?
Do you want to be a developer, a software tester, do you prefer the business analysis side of things, do you like finding and resolving bugs as you would in a Support Role etc ?
If you decide on the technology you would like to work in, maybe thats ASP.Net, then buy 2-3 books starting off with the basics and then into the more complex stuff. You'll get through a book in a week or so and I always found I learn a lot from them if you choose the right ones. Amazon.com is handy, you can read peoples reviews on the books so you know you are buying a good one.
Finally I would say try to to look ahead, sometimes you think that right now you dont have the skills and that you are humped, but really it just takes 1-2 years to gain really good skills and experience if you work at it.