So you've just heard speakers that blew you away

You need to understand how and why they sounded so good when/where you heard them and then assess how they will work in your room with your listening habits. THere will be differences with teh same setup in any two rooms.

Knowledge is key. The more you understand about why something sounds good or not when you hear it, the better. THen you can apply that knowledge in your specific case to expedite good results. It takes time and lots of listening and asking of questions to get to that point though, so don't rush it and drop a bundle too soon.

The other approach is to set a practical initial budget to take your first best shot, but plan to tweak and change from there as needed over time. BUying/selling used will help provide flexibility to change tweak and adjust as needed without taking a huge financial hit. High end audio can be a money pit, worse than a house for what you might get in return, so do not jump into the deep water too fast.

They must push an enourmous amount of air to blow you away :-)

Mapman hit the nail on the head.

I've done that a couple times, complete with the selloff of parts (and later all) of my esoteric high-end headphone collection (Qualia 010, L3000, etc). The 1st time was a bad call. The 2nd time worked great, because by then I had a better handle of what I liked speaker-wise, and had owned/heard enough of that brand's models (Tannoy DC) to know I should stretch towards the biggest/best one I could afford -- Kensington SE, at the time. The in-shop audition definitely blew me away. Though after purchase, there was a rough patch for a few weeks as my supporting gear was not quite up to par (decimated after raising funds for the speaker, really) and I was figuring out placement issues. However, I do remember it all snapping into place with a particular placement and an old Eico HF-87 (w/ cheap EH EL34 tubes, no less), and it was glorious! Three very satisfying years followed, until I upgraded to a even bigger model in the line (Canterbury SE).

The speakers ARE the most important piece of a system, so I do think it's fine to plan around those first and bring the supporting gear in line a piece at a time as possible. Good speakers will plainly reveal individual changes, and let you know whether it was a good move. Good speakers can also play nicely with the right selection of "budget" gear. To me, a speaker touted as demanding only the very best in recordings and gear is not a speaker I will tolerate (read: usually the wrong kind of bright, analytical, bass shy, or all 3).

In retrospect, I approached this hobby without a sufficient amount of patience for far too long. And the cost of this is significant in time, money, and frustration.

Carefully measure each step you take financially and take your time.