The Dinner Party

Professor Egghead was talking to a colleague who told him about a dinner party he had attended with his wife. The colleague told him the following things about the party:

1. There were four married couples present.
2. Each person had a unique hobby.
3. The eight people were seated around a dinner table with the host and hostess at either end and three people seated on either side.
4. Only one married couple were seated beside each other.
5. A man was seated on either side of the hostess.
6. A woman was seated on either side of the host.
7. The hostess likes to ride horses.
8. Donna collects stamps.
9. Carol and her husband were seated on the same side of the table.
10. The piano player was seated next to his brother-in-law.
11. The person who grows roses was seated next to the person who does needlepoint.
12. Frank was seated directly across from the person who builds model planes.
13. Harold is seated to the immediate right of the hostess.
14. George and Betty were seated directly across from each other.
15. Alice is married to Edward.
16. Donna's sister-in-law is seated directly across from Carol.
17. The piano player was seated next to the hostess.
18. The stamp collector's husband was seated across from the model plane builder.
19. Carol was seated immediately to the left of George.
20. Alice is married to the fisherman.
21. The person who does needlepoint was seated across from the actress.
22. The actress was seated immediately to the right of the host.
23. The fisherman was seated across from his sister.
24. Frank was seated next to Edward.

What was each person's hobby, and where did they sit?