It's definitely not basic, so don't worry abou tthat. However, I'm very surprised you searched and didn't find the two following blogs especially when I've already helped you a few times and when my blog on this topic is directly referenced at the top of Itay's blog that you referenced. The other blog is linked from my blog and links back to my blog. None of that showed up in search nor on Itay's blog when you read it?
InfoPath - Get user information without writing code (extended)
Use the Contact Selector in InfoPath to get user details – no code required
I'm curious to get feedback on why you didn't notice my blog reference on Itay's blog at the top so that we can try to make it more noticeable. I'm also curious as to what you used for search terms and which search engine you used, because my blogs get all sorts of hits from search engines with all sorts of crazy combinations of words - all of which I would assume you used to some degree or another. Lastly, I'd be curious as to how you hadn't noticed my blog so far in my signature when helping you. If you're working with InfoPath, asking for help, and I'm helping, then I think my blog is a pretty likely destination for you in the future. It's full of advanced SharePoint-integrated InfoPath information that is all without code, so you'd probably like it.