The Times vary, it depends on the level of the fruit tree you plan on planting. but they usually take a good while.
140 Minutes.
about 200 years
lots of trees like oak
2 years
Oak trees will not grow from cuttings they grow from seed or are grafted.
you can't get free oak planks on runescape now stop being a noob and make them yourself. -.-
There are 3-5 oak trees in rimmington
Cut oak logs
There are several types of staircases. For example, an oak staircase requires no nails - but it requires 10 oak planks and 4 steel bars.
You don't buy oak trees. You can buy oak logs, or oak planks. You can also buy oak seeds, which in this case are called "acorns". Prices in RuneScape change all the time, since they are mainly driven by supply and demand. You can find updated prices here: at the top of the main RuneScape page, there is a kind of menu; select "Community", then "Grand Exchange".
Oak longbows can fire up to Mithril By snerderwerder (nickname)
You can buy bagged oak trees from the Garden Supplier in Falador park.
No. Poison oak is not a tree, but a vine. Oak trees grow from acorns.