First click on this Lonely Planet article in pdf http://www.lonelyplanet.com/shop_pickandmix/free_chapters/central-america-6-getting-started.pdf  

  if you have never been to Central America before (perhaps Central America, 7 small countries, one big adventure, would be a nice alternative to Thailand this year, did you know some Highland Guatemalan Indingenous languages (or dialects if you prefer) and some textile designs are similar to those of Thai Hill Tribes????)

and here is my Primer for First Time Travelers to Central America, an informal information bloq, Anyway here is my Central American "travel primer"

https://docs.google.com/Doc?docid=0AYZawEgpPr-NZGZiN3o4OXRfMjdocWQzZmhjYg&hl=en

A primer for those traveling/volunteering/possibly relocating to El
Salvador, Guatemala, Honduras, Nicaragua and the rest of Central America for the first
time.

those of you who have any questions on Mundo Maya (MesoAmérica) - Mayan World, Colonial Era and the modern era please message me.

Traveling in Central America is generally hassle free if you plan ahead for your journey, from a week to several months. here now exist non profit Hospex Portals such as 'Couch Surfing' (Thousands of native Central American members who will either host you at their homes or meetup with you) www.couchsurfing.org/ is the best of the Hospex genre (160 countries represented), Live Mocha, a social network for language learners and teachers, in case you may have no Spanish skills, trade free tutorials English & Spanish, with native speaking members www.livemocha.com/ , as well for a list of Spanish Schools in Latin America and free on line spanish beginners course click on o: www.123teachme.com, finally if you require a native guide, for cutural or eco excursions, seeking a jungle lodge, eco-hotel or oher unique lodging place click on o Localyte.com www.localyte.com and type in your destination (170 countries, thousands of regional destinations represented) and use the "ask a question" application.

Of course purchase an up to date Guide Book, specific to the country or region where you are traveling, your local book store, travel section or browse online amazon.com read your guidebook before departure.