Sumatra Help

I really think you need a guidebook.

Till you get one, several suggested sights are listed in the Indo link in my signo line.

There are no longer security worries in Aceh/Sumatra.

Check out my photos below of my trip to Indonesia last year where I spent 3 months in Sumatra.
The well trodden trail in West and North Sumatra is below.

West Sumatra- you can visit Bukittinggi, Lake Maninjau, there is a pleasant 2 day between the two I did last year staying at Anas Homestay overnight in the jungle.
Lots to see in that area. Read Emma's report of her 3 months living in the area from late Mar-June 2006. West Sumatra Blog
South of Padang in West Sumatra is another area that I really enjoy visiting Painan- see my photos as well.

In North Sumatra there is Bukit Lawang, and from there you can do a 2 hr motor bike trip with driver over very rough road to Tangkahan. Check out this forum for info'
Bukit Lawang Info'
ForTangkahan Info' read here.
Also from Medan you can do a bus trip through to Kutacane in south Aceh and onto Ketembe. On that same bus trip you can stop for a few days in Brestagi a lovely cool area of Sumatra.
In Ketembe you can go on treks into the jungle and see wild orangutans in the jungle compared to the tame semi domesticated ones at Bukit Lawang.
From Ketembe it is quite easy to get a bus up through Central Aceh to Blangkejeren, Takengon- worth a couple of days here, Bireun and Banda Aceh.
From Banda Aceh you can head over to Pulau Weh for diving, snorkeling and just plain relaxing in litte primitive huts by the water in Iboih.
Then there is Lake Toba.

I was in Aceh for 18 days last year and absolutely loved it. You no longer need any permits and travel is easy and the people really friendly.
Aceh Report
Pamela.

As the above posters have stated, there is no security issues in Sumatra, it's a great place, and a month in Sumatra will definately be long enough to experience some amazing places.

I really enjoyed Nias (it still is one of my favourite places in Indonesia - though as a surfer I am biased) and it is a bit different from the mainland, however if you don't surf you'd want to be REALLY keen on the culture otherwise you won't find much else to do.

I enjoyed Nias for its natural beauty, strolling along the breathtaking beaches, fishing etc..
Tried to surf but gave up, those waves were savage! Swallowed to much salt water and got pretty bad bruised. (Ouch!)
Those traditional villages, they look impressive but that's about it. You couldn't just walk into them like a welcomed guest.
Pay for entrance, meet the village head where I was again asked for a fee, sign a guest book, tour around some old house where they tried to sell me silly souvenirs. Not my cup of tea. ;-)

West Sumatra is very unique and accesable. It has a matrifocal culture and you an feel it if you get to know anybody or hang out a bit.

As above repies say..there are zero security issues in Sumatra....i spent just over a week in Banda Aceh earlier this year - not nearly long enough!!!!!!

I can't compare to anywhere else in Indonesia, but Aceh Province is tremendous. Friendly, helpful people..always with the open smile when they greet you. Spent most days solo m/biking as far as I could and never any problems, but always help at hand if needed - I got lost once!!!! Lots of vehicles banging their horns with a friendly smile from the occupants.

I believe the province has been classed on TT as "quite conservative", in comparison to other parts of Indonesia..... no alcohol (unless you locate a chinese owned shop!!) and all muslim males should be in prayers every friday (between 12 and 2pm- if i remember correctly).

It's a wonderful area to visit and i feel sorry for the people who decide not to visit - they definately lose out.

Have fun in whatever you do.