As Dave mentioned above, the biggest false economy is going with Hornby track (in particular the points), Peco make a very good product if you're not going to scratch build (I neither have the time or the inclination). When I lived in the US I bought all my Peco track from a tiny local model shop although my rolling stock had to come from the UK, so in addition to Hattons you can also look here https://railsofsheffield.com/default.aspx I've found their customer service and speed of shipping exceptionally good in the past - but I would encourage you to whenever possible support your local model shop, times are tough, I saw 'The Train Man' from Portlaois and Dave at the show at the weekend working hard, and it's guys like these along with the Marks Models etc we need to support with our hard earned cash. I'll be wearing the road thin between Castlecomer and Portlaois thin over the coming months.
It's a great hobby, changing with the times and so it has something for everyone - I like the technical side, DCC, and the scenic stuff - you can become immersed in your own world while it's gone to heck in reality - escape. Good luck with it, don't get frustrated, ask the questions because everyone will have been there at some point to some degree and the end result is very, very satisfying.