tu7fa!. Seeking knowledge is - to some people - an appetite which can't be fulfilled by "knowledge sandwiches". It is obviously true when God says: "say: the spirit (cometh) by command of my Lord: of knowledge it is only a little that is communicated to you, (O men)" ... & ... "say, O my Lord! advance me in knowledge."
For further knowledge, I think the internet is one of the free "classes" which we can attend, and are open to us with no limits or boundaries. Books, newspapers, television, radio, etc.. are all means of education from which we can aquire knowledge and experience.
One more way I like and a person may implement to develop his/her skills is to "throw" yourself in "the sea of life" and -- definately you'll get hurt and scratched here and there, or maybe get your nerves dance, or suffer from that dark color under your eyes, and bla bla bla ... but in the end you'll have something new to put in your CV.