rates

I’m a Senior in highschools who is planning a trip to Europe during the month of June, and I have a few questions about airfares. I’m departing from Spokane, Wa (GEG) and I’m hoping to fly in some where near Krakow, Poland (But I’m flexible, and willing to take the rail there).

• When is the best time to book a flight around this time frame? ie. is March 29 better than the 1st, or is monday better than friday.
• Where can the best deals be found for flights Europe?
• Which airports are cheepest to fly into? (I noticed Paris seems more expensive than most)