Top Spin 3

you need 8 people (or multiple accounts) - 4 people get the achievement per session (men's and women's tour).
there are always teams of two with numbers assigned to them so it's easier to keep track.

1
8

2
7

3
4

5
6

be sure you have a character at around lvl 30 - but, i managed to match up with a lvl 39 pretty easy. (if you can't match up instantly then the one who's loosing should quit out and search again)

so, the tournaments work like this:


1 vs 8
| |
1 vs 3 5 vs 8
| | | |
1 vs 2 3 vs 4 5 vs 6 7 vs 8

then switch to mens/womens:

2 vs 7
| |
2 vs 3 6 vs 7
| | | |
1 vs 2 3 vs 4 5 vs 6 7 vs 8

while the finalists play their match 3 vs 4 and 5 vs 6 can start the first round of the next tournament and while 1vs2 and 7vs8 is going on they can start the first round of the next tournament and so on... there's another way too, where every pair starts on another tournament...

so the first round dropouts (4 and 6) will be finished early and can leave then (after the mens tournaments) or trade quick match wins for points:

just search in quick match and as soon as you see the picture of your opponent one quits out. the winning player should get more points than from a fully played match.

-----------------------------------------------------------------

- for the "The Season's 5000s achievement":

you'll get 2800 points for reaching all 4 finals and if you split wins 2:2 you'll have 4400 after that. so you'll have to do either some quick matches or play some of the remaining tournaments to reach 5000.

- for the "Win $1,000,000 World Tour Prize money":

i got the 1million dollar achievement after i reached the 4th final on the mens side.

This actually means you have to reach 4 GRAND SLAM finals. You don't have to win those finals, but you do have to play them. And also in just one season.
Can be done by either being a (very) good player or by help of some friends.

just win the 2nd round of slam, to reach the final,
no need to play the final.
could boost it with 2 friends only, or 2 accounts