This is a simple one.
Very simple.
DO NOT go and buy them out right from a rare material trader.
DO NOT buy them from other players.
This is wrong.
Very fucking wrong.
Just have them crafted by an Artisan (aka, a [Materials] guy).
Crafted for a cost of 5 Plant Fibers and 200 gold.
The only Artisans that craft Linen are in Prophecies and EotN. Here are their names and locations;
Prophecies
1) Artisan Daved in Old Ascalon
2) Artisan Kristan in Regent Valley
3) Artisan Rudger in Ascalon Foothills
4) Etham the Artisan in Nebo Terrace
5) Artisan Sivan in Talmark Wilderness
6) Hadasha the Artisan in Mamnoon Lagoon
7) Sennat Sen in Salt Flats
Eye of the North
1)Shalgrim Stonehart in Varajar Fells
The closest Artisan (to a town or outpost) that crafts Linen is Artisan Kristan just outside of Fort Ranik. For those who can't get there try Shalgrim Stonehart in Varajar Fells (EotN) or Etham the Artisan In Nebo Terrace (specifically the Nebo Village there).
Remember that having Rare Materials crafted by artisans is generally (almost) always cheaper than flat out buying them from a Rare Materials Trader.
Ok,
That's that for this week.
GL/HF,
Atty