Try www.sncf.com website...I think they have maps

Paris stations are all over, and the station you leave from depends on where you are going. I wouldn't worry about daytrips, just find an apartment in an area you like and take a bus or the metro. You won't have any luggage!

No, you shouldn't use that as a criteria. There are many train stations in Paris (about 4-6), but generally you can't just leave from any train station to go somewhere. They service different lines and different parts of the country--most of the time you have no choice for a specific trip. You may plan trips leaving from Montparnasse, Est, Lyon or Austerlitz, or just the main RER stations.

Also, Paris isn't that large (about 4-5 miles N/S and E/W) that you will be very far from any train station if you choose to stay in the central Paris area. Sure, it can be nice to just walk to a train station for a day trip if you are within a couple blocks, but that is actually less important for day trips because you won't be carrying that much. Just find an apartment you like at a good rate. It will be much more important to choose the area based on how well you like it for other matters than proximity to a train station. Do pick one not too far from a metro stop.

Tourism may be down a little this year, but it is rather late to be booking an apartment for July, so your choices will probably be limited. I try to book an apt. for summer at least 6 months ahead in Paris. I'd suggest you consider arrondisements 1,4-8 or 11 or 14. There are others or parts of others that would be okay, also, but that's a rough guide.

If you are going for a while and plan an investment like renting an apt., I think you should get a map of Paris ASAP to plan your stay in Paris. It sounds like you don't have one, as train stations are marked on them, and you can see proximity to tourist sites, metro stations, etc. I would never book an apt. without seeing where it is located on a map.

As the others have said, there are several train stations in Paris:
Gare Montparnasse, Gare de Lyon
Gare du Nord, Gare de L'Est, Gare St. Lazare, and Gare d'Austeritz. There is even a Gare Bercy for some train departures at night to the south and east of France.

If you wanted to go to Fontainebleau, the quickest trains leave from Gare de Lyon. If you want to go to Vernon to visit Monet's estate in Giverny, you need Gare St. Lazare, and if you wanted
to go to Chartres you would need Gare Montparnasse. So obviously you cannot be close to all of them because they are scattered all over Paris.
If you had to group them, Austerlitz and Lyon are fairly close as are Gare du Nord and Gare de l'Est.

I recommend, as did the others, that you select a place close to local transportation rather than thinking about leaving town. Five days in Paris is just about enough to see the highlights. I have been there a total of 12 days in the recent past and I have quite a few attractions left on my first dance card.

As others have nicely covered, the train stations are spread out around Paris (you do need to get a good map asap!). I would pick which neighborhood was of greater interest to me, each arrondisement has its own personality ... and try to be near a Metro stop. That will serve you much better daily, than any one train station.

Do you have an apartment or hotel reserved? Or you mean you plan to find a place to stay after you have arrived in July? Just curious.

Due to the "saturation" of the Paris Metro you are never more than a few minutes-walk from at least one Metro station. Anf if you're willing to use the Metro you can get to any SNCF rail station very easily.
Go to www.ratp.fr for interactive maps, directions, and a trip planner. Concentrate on your accommodations needs first..public transport will be an easy second concern.

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