This site has a lot of the classics and more. Many songs are available for free as pdfs with either guitar and/or piano sheet music as well as lyrics. Some lyrics are in Hebrew others just in English. http://www.totshabbat.com/Passover.html
This site is an unbelievable resource of hebrew songs – some 4000 or more. http://www.hebrewsongs.com/search.asp The site offers in most cases both transliterations as well as hebrew words for the song. You have to scroll through an alphabetical listing, but its pretty easy to navigate and the information is great.
Learn the aleph bet with fun cartoons and silly things to help you remember the letters. http://www.cartoonhebrew.com