Unfortunately I have no idea how the product will be packaged, are wap sites deployed in wars? how are they different from other projects. I searched the web but i normally get Wap tutorials on how to use wml tags. I need a guide on how to start and how to test.
While a web app can emit WML as appropriate without problems, the principal difficulty is that WAP generally needs a gateway to negotiate between the browser and the server; see Wireless Application Protocol and WAP gateway. The latter page links to a couple of open source gateways, although -given that WAP is mostly obsolete- I wouldn't expect them to still be supported these days.
... haven't found how to call api's. How are servlets (services API) invoked in WAP?
I'm not sure what you mean by "API" in this context. A servlet implements an URL - that is what the handset accesses.
By the way, reading that Wikipedia WAP page I noticed that WAP 2.0 basically consists of XHTML MP accessed over HTTP - no need for any gateways. So if supporting WAP 2.0 is sufficient, then development and deployment become much easier.