Good Tea Shop in Tokyo

I will leave Japan and return to my home country soon, so several relatives of me are asking for some special omiyage or souvenirs from Japan - mostly tea.
Can anyone recommend a good store in Tokyo that sells different types of tea (besides the typical Matcha also some more rare ones)? My aunt and grandma are asking for some special Japanese tea types, so I would need a shop with a bigger variety of tea.
Thanks in advance!

The food hall of any big department store should have a decent selection of tea.

Green tea
Ippo-do
http://www.ippodo-tea.co.jp/en/index.html
Black tea
Afternoon tea
http://www.afternoon-tea.net/eng/shop_list/index.html
Lupicia
http://www.lupicia.com/global/
Karel Capek
http://www.karelcapek.co.jp/shoplist

A good tea is always expensive.
I don't know about your budget but all department stores organize a summer time gift sale called Ochu-gen gift, this time of the year so I recommend you to visit there(normally held on upper floor).
I recommend something like this.
http://edepart.7netshopping.jp/ss/item/00100010499999452059.html
The package include about 20 different teas.

or, 9 teas include leaf teas
http://www.takashimaya.co.jp/shopping/food/0400000042/0400000047/-/ps_...

or, 3 teas bag.
http://www.takashimaya.co.jp/shopping/food/0400000042/0400000047/-/ps_...

The few centuries old Kyoto based Ippodo has a shop in Tokyo Marunouchi where they have a tearoom for you to try their teas.

Have not been to the one in Tokyo but the staff in their Kyoto shop can speak English to help you with your selection of teas. You can check for more details from the link given by haro1210-san earlier.