Accessing Webservice using SharePoint server object model.

Hi

We have a requirement where we need to interact with a web service and read the flag being retrieved (true / false) and interact with  other web service to update the data base.

This need's to be achieved using SharePoint server object model and there is no scope for using BCS.

Could some one please share me relevant info / article which help's understanding the method to achieve this.

Thanks In Advance,

Venugopal