We are a couple going to Cusco at the beginning of August. From there we want to go by bus/train to Titicaca and La Paz. (3 weeks).
Do we need reservation for a B&B or hotel in Cusco or you get a better deal once you get there?
Do you need to go with a tour group to Machu Pichu?

You do not need to go with a tour group to MP unless you want to do it by hiking the Inca Trail. There are no signs or interpretive materials on the site of MP (thank goodness!) If you can't follow along on maps and guidebooks, you will enjoy the experience better by hiring a guide but they are available at the entrance. You don't need to go on a tour and I don't really think it is as enjoyable to being escorted around the site in a large group. This trip does take some planning, there are plane trips Lima and Cusco, taxis and trains between Cusco and MP. If you're not up for that then you can usually find good package deals from agents.

I would recommend to read some of the trip reports here on Fodors as well as a guidebook. The best thing to do as far as the altitude is to leave Cusco as soon as you arrive and go straight to the Sacred Valley to spend a few nights. You can then take the train or bus/train to MP from the town of Ollantaytambo. Ollanta or what a lot of tourists seem to call "Olly" is a great spot to stay. If going as a couple I think the El Albergue hotel is a perfect spot. They have a website and English speaking staff. #1 rated hotel in Tripadvisor. After your visit to MP you can then go to Cusco for a few nights and onward to Titicaca.

Going to La Paz requires a visa for Americans. If you are a US citizen you might decide it's not worthwhile.

www.elalbergue.com

I doubt you will get a better deal just by turning up in Cusco. The hotels and hostals tend to have fixed rates and are not generally willing to bargain. we spent a couple of months in Peru in August and September and in Cusco particularly, it wasn't always easy to get a room in a decent place. I would book in advance at least for your first night.

I agree with mlgb's comments re staying first in Ollantaytambo as the altitude in Cusco can be a real problem for some people if arriving directly from sea level i.e. Lima (At least it was for me!)

I would suggest that you book your onward travel to Puno (for Titicaca) as soon as you arrive as the better buses and the train can get booked up a few days in advance at that time of year. (We used the Inka Express bus which visits a few sites along the way).

A link to our blog with some more info. Entry#56 Onwards covers Peru.
http://www.travelpod.com/travel-blog...ai/1/tpod.html

Thank you for the info. We are canadians, I hope we don't need a visa for Bolivia.
We have the tickets already and 3 weeks to spend between Cusco, MP and Titicaca and La Paz.
Can we do a shorter version of the Inca Trail? 2-3 days?
Where do you book that?
Thanks again.

If you are American you need visas for Bolivia; they cost $135 each.

I don't think Canadians need visas.

Hi yorkmemo,
Here's a couple of sites...maybe they have the info you need. http://www.incatrailreservations.com/
http://www.incatrailperu.com/

Have fun,
Michele