You should choose your speakers first, then choose an amplifier according to the needs of your speaker, room and intended use.
There are several considerations to consider. Are you looking for 5.1, 7.1 or are you OK with starting with a REALLY good 2 channel system to start then and sub, center and surrounds later, which could get you much higher quality components over time?
Are you looking for floorstanding, bookshelf or on-wall speakers?
What are your expectations for low frequency effects and bass in music? A good subwoofer can tie up a good portion of the budget, but is often recommended.
The answers to these questions can help narrow down the search, then you will have to go out and listen to speakers to further define what you like and don't like regarding the way a speaker sounds. Based on your preferences, there may also be internet direct brands that will suit you well.
Oh, and welcome aboard. Don't rush the speaker selection process. Take you time, enjoy the hunt.