I too can highly recommend the Hotel Euro, our group have been for the last 2 years and each time the hotel has been excellent.
With regard to tickets, I booked ours via ticketpotal https://www.ticketportal.cz/ and found it pretty straightforward to use as you can change the language to English. You print the tickets off at home.
We have sat in the main stand, just either side of the start line and had a fantastic view, you will wherever you sit to be honest. We sat on benches that are numbered so depending on who you are sitting with and close to, it can be a bit of a squeeze.
If you are able to get on the front row, its much easier to catch the attention of the girls bringing the drinks round!
I believe our tickets cost £25 - £30 for both meetings last year, with the Friday night meeting only being a few pounds.
You'll have a great time, lots of food and drink in plentiful supply and great speedway.