Well, you're arriving on the first floor of T2. There are some coffee shops you can wait for ur friend. Make sure you are going to the same one.
if you dont wanna spend any money, there are some benches you can kill some time. (you can tell him to meet you in front of the ICBC Bank, turn right once you exit)
If my memory serves me right, your exit should be EXIT 3-5, so there should be a coffee shop near there,
here is some info that I copied from the website.
EXIT 11-13 is for domestic arrivals.
BAFS-Exit 3-5 coffee shop, at the public area of the first floor
Open hours: 7:30--22:30
Contact number: 010-64598529
Location: Between Exit 3 and Exit 5 at the public area of the first floor
READ THE PRICE BEFORE YOU ORDER! THE PRICE THERE INTEND TO BE REALLY HIGH COMPARE TO THE CITY. you can always order the cheapest-"mineral water".
Or you can find a place on the website.
http://www.bcia.com.cn/en/index.jsp
If u're taking a cab with ur friend to a hotel. Make sure no more than 150 Yuan should be paid.
If you have other questions, I'm willing to help.
Enjoy ur stay in CHINA!