Stackoverflow is a great resource, regarding general software development questions. Dynamics NAV is rather a niche product, here you will hardly find lots of info, concerning development for it.
I think that all (or most) information concerning specific Dynamics NAV tools (there are not so many) can be found (and should be looked for, in the first place) on the Microsoft Dynamics PartnerSource site. If you have no access to it (it restricted to partners only), then I can recommend www.mibuso.com forum - one of the biggest resource of Dynamics NAV information.
If you are a member of Dynamics NAV partner team and have a NAV development license (which gives you access to NAV development tools), then all that is said by me is obvious for you and here you could find a help for the rest of your needs and Visual Studio is luckily the main needed tool.