Can I make my beer sweeter before botteling?

I am making a partial mash oatmeal stout. 1 week in primary and so far 1 week in secondary. I am at my finale gravity but I would like it to taste a little sweeter. can I add something at botteling time or will another week in the secondary help sweeten it some?

Lactose
Thats what they add to milk/sweet stouts to give them that sweet creamy taste.
I have seen recipes that add from 4oz to over a pound of lactose in a 5gal batch. I havn't tried it yet myself so I can't give recommendations but you could add a small amount to a glass until you figure the right ratio for you then scale it to your 5gal batch.
Lactose is not fermentable so you will still need your bottling sugar.
Another option is to add something like Splenda, which is an unfermentable sweetener.

Craig

You could increase your mash temperature to increase unfermentable sugars.

Leave it in the clearing tank for a month, then draw off a pint. Add a tsp of lactose and check the flavor. If that's good, add 4 oz. of lactose and bottle.

You could try sweetening it now, but it's green & you'll probably over-sweeten.