Bordeaux has an array of hotels for every budget. I had made reservations before we left Canada, however it would not have been a problem arriving in Bordeaux without a reservation. The only time that you should make a reservation is during the annual wine expo in June - the dates vary from year to year.
I ended up choosing the Holiday Inn City Centre because it was advertised as a four star hotel in downtown Bordeaux with competitive rates (70-100 euros per night) and I could collect frequent flyer points. Hint of advice: before booking a hotel, check a local map to see exactly where it is in proximity to major attractions. Although it says on the Holiday Inn web site that this hotel is 0 km from the city center, it is in fact a 30 minute walk and 5 - 10 minute taxi ride to the center!
The hotel is typical of a chain property: walls and furnishings in generic pastel colors, pleasant staff in crisp uniforms, a restaurant that you would never eat in unless you were truly desperate, and modern conveniences including air conditioning and private shower/bath. The room was spacious for European standards, clean, and quiet. The view was okay, much better than those with rooms that face the front. My only major complaint was that the hot water heater for the hotel broke the second night we were there so I was denied one of my favorite pleasures, a frothy bubble bath.
If you intersted in staying close to the train station then this is an ideal choice; but because Bordeaux does not suffer form a shortage of hotels, I suggest you look for a hotel closer to the major attractions and rue Sainte-Catherine. Should your heart be set on staying at a Holiday Inn there is another one in the business district (Meridaeck), which is closer to the real city center.