I will be soon in the DR with a laptop cause I need internet access, is there a posibility of contract a dial-up account and access it from any phone while traveling?
No. This service is only provided at the more pricey business hotels in Santo Domingo. Otherwise, the hotels offer internet centers where people can check their hotmail/yahoo type accounts. Expect to pay about RD$80 for half an hour.
Several "Internet Cafes" will let you hook up your computer to their system (lline) if you need to do soome online work. You'll have to check with them when you arrive.
Contact http://www.codetel.net.do or http://www.tricom.net for information on setting up a local connection. It might be an expensive option for a short term. Then you can connect if someone lends you a line. That person would need to have a VIP connection, at least. It's possible, but probably much easier to have a previously set up mail service so you can view your mail from any computer.