To get to Machu Picchu, your starting point is the City of Cusco. There are flights to Cusco from Lima and other cities in Peru. Once in Cusco there are different options: you can either drive for a couple of hours and trek the Inca Trail (4d/3n), take the train part of the way and trek the One-day Inca Trail (5 hour walk) or take the train all the way (4 hours).
You may also want to consider spending a few nights in the Urubamba Valley (also called Sacred Valley), the staggeringly beautiful Valley that lies north of Cusco on the way to Machu Picchu. For more details on what to do and see in the Urubamba Valley, please contact us. From the Urubamba Valley, specifically in Ollantaytambo, you can take the train to Machu Picchu or start your drive to the start-off point of the Inca Trail.
You can go to Machu Picchu for the day, but we don't recommend it. It tends to get very busy during the 4-hour time slot between incoming and outgoing trains in the middle of the day, and the crowds detract from the magic of the experience.
Once in Machu Picchu, if you can afford it, you should stay right at the only hotel by the ruins: the Machu Picchu Sanctuary Lodge, and it is expensive!!! There is more affordable accommodation in Aguas Calientes (where the train station is located) which is at 30 minutes away from the ruins by minibus on a winding road uphill. It is not a very pretty place and there is really nothing to see. For most guests it is merely an overnight spot.