Clement Wood's Poet's Handbook covers about eveything you could want to know about poetry and how to write it. I have the 1942 edition. But I'm not sure I'd recommend you use any book right now. You are doing just fine without one. Finding out how someone else thinks you should write might ruin your style. This book is not a how-to book, but a reference book, and it features examples from the author's own poems and other famous poets. The book defines and explains the different types of poetry. It will help you study the techniques of others, all the poetic patterns and devices poets use. It's 464 pages and indexed.
I appreciate good poetry, but I don't consider myself a poet. I sometimes write light verse or blank verse, but not as often as when I was younger.