On this website you will find all the officials resources :
Be sure to visit the official website
Ticalc is the reference, the community major website.
If you want to visit only one website, visit ticalc.org
Cemetech is probably one of the most active website about TI84 plus programming.
The leader even published a book about TI84 plus programming !
Go visit cemetech
to learn more about hardware and programming the TI84 plus.
Omnimaga is well known for his basics developpers and some incredible productions.
A lot of axe and assembly programmers are frequently posting here too.
Say hello to Omnimaga
Tiplanet is the french major website about ti 84 plus.
The site is entirely translated for english native speakers
The website provides a lot of news and hacks.
Have a look at Tiplanet
Ti freakware provides a lot of resources especially tutorials.
Visit Ti Freakware
This is a website mostly about programming.
Currently, not a lot of activity here.
A nice french forum with some assembly development activity.
This is a partner site.
They provide helps, tips and tricks and sells ti 84 plus calcs.
Please do not forget to visit calculatorti