The cheapest way to get to the frontier is by combi. Combis leave when they get full from the corner of Abad Puell with Simón BolÃvar, ask anybody at the main street to find them. If you get to the Emtrafesa bus terminal, you're just a corner away from the combis. They will let you off at the peruvian immigration control, where you'll have to get your passport stamped. After that you'll have to make your way to the ecuatorian immigration, which is some kilometers away. If you're around the peruvian border control between 9 and 10 a.m. you'll probably see some transnational buses Rutas de América, Ormeño, etc. waiting for their passengers to get their passports stamped: it is not a bad idea to talk to the driver to see if you can join the group until Guayaquil for some dollars. Otherwise, remember: be EXTREMELY careful with taxis around this frontier.
A much easier and safe way, but also much more expensive, is to take a direct bus from Tumbes to Guayaquil, that will wait for you in both immigration offices. Ormeño (http://www.grupo-ormeno.c...) to Guayaquil daily & Quito weekly, CIFA Tumbes to Machala, Guayaquil in Ecuador & Transportes Loja Piura to Machala, have international buses to Ecuador. Tepsa runs buses to and from Lima for about $31 or 93 soles.
Be careful not to get scammed by taxi drivers telling you that the Cifa terminal is closed and that you need to take a taxi to the border. The Cifa terminal used to be at 540 Av Tumbes as mentioned in the Lonely Planet guidebook. It has since moved down the street, somewhere in the 900s on Av Tumbes. A taxi driver scammed 20 soles out of me by showing me old information that said the terminal was at 540. The terminal is signed as Cial, but it is also Cifa International.
There are kombis along the coast to neighbouring beach resorts, & national buses run frequently along the Panamerican Highway from the frontier with Ecuador & Tumbes to Mancora, Piura, Chiclayo & Trujillo, for Huaraz, Cajamarca & Chachapoyas, Chimbote for Huaraz,& Lima.
The CIFA terminal is located sort of outside town and you will need a moto taxi to get to the center of Tumbes if you want to catch the Cruz Del Sur bus to Lima. The moto taxi should cost you $1. Another option to get to Lima is to book a cheap flight. Peruvian airlines has flights to Lima at 3pm and costs around $95 one way. There is a travel agency next to the Cruz Del Sur terminal that can book a flight at short notice. The airport is located a fair bit 15 mins away and costs 20 soles or $7 so keep this in mind! The flight will save you about 20 hours on a bus!
