Hi.
 I'm new to salesforce , And I have a requirement where i got to integrate website with salesforce.
I want to have a solution which can be used further without back and forth.

In my view I want to use webservice, Since I'm new to salesforce Im unaware how approach.
Looking for kindstep by step help/approach from this community.

Scenario

I'm  looking for a solution where user's signup info from website posted should be saved in contact object.
How do i have to appraoch this solution ? right now i dont have client website platform information whether it is created with only scripting or along with programming language.

Is there a similar solution where we can have salesforce web-to-lead like solution (encrypted in visual force script added to webmaster page of website)?

Can we create webservice and expose ?
Can we consume webservice from external system using wsdl?

Looking forward for you step by step procedure which can lead me to solve the above problem.

Thank you
Abrar Waheed.