I read the Vorkosigan Saga last year (over a dozen space opera novels free for download, why not?) and it was a lot of fun. There's a new book in the series being published later this year, and am looking forward to.
Cordelia's Honor, a collection of the first 2 books. Or so I've been told.
It's actually the first book and the seventh book. However, the seventh book is a direct sequel to the first book, which takes place before most of the rest of the books... it's complicated.
You see, first, there's two phases to the Vorkosigan saga.
First there were four books that are all in the same universe but have varying degrees of relation to each other.
The Warrior's Apprentice stars Miles Vorkosigan, the son of the protagonist from
Shards of Honor, but
Ethan of Athos rotates around an obscure part of outer space and
Falling Free takes place many centuries prior to the rest of the three books.
After this point the series is mostly a series of sequels to
The Warrior's Apprentice, with
Barrayar, a sequel to
Shards of Honor, being the only exception.
And while the rest of the books mostly chart the life and career of Miles Vorkosigan, those also weren't written in order - sometimes jumping back a few years to fill in gaps implied in earlier novels.
As far as the omnibuses go, up until
Miles, Mutants and Microbes they cover the series in the in-universe order.
...anyway. This means there's basically two ways I'd recommend reading the books: In publication order, or in order of events as they 'happened.' Here's some lists (found myself habitually writing lists for book series these days, makes it a lot easier to keep track of where I'm going):
Publication order:
1.
Shards of Honor
2.
The Warrior's Apprentice
3.
Ethan of Athos
4.
Falling Free
5.
Brothers in Arms
6. "The Mountains of Mourning"
7. "Labyrinth"
8. "Borders of Infinity"
9. "Weatherman"
10.
The Vor Game
11.
Barrayar
12.
Mirror Dance
13.
Cetaganda
14. "Dreamweaver's Dilemma"*
15.
Memory **
16.
Komarr
17.
A Civil Campaign
18.
Diplomatic Immunity
19. "Winterfair Gifts"
20.
Cryoburn
In-universe order:
0.
Falling Free, "Dreamweaver's Dilemma"***
1.
Cordelia's Honor omnibus (
Shards of Honor,
Barrayar)
2.
Young Miles omnibus (
The Warrior's Apprentice, "The Mountains of Mourning",
The Vor Game)
3.
Miles Mystery and Mayhem omnibus (
Cetaganda,
Ethan of Athos and "Labyrinth")
4.
Miles Errant omnibus ("Borders of Infinity",
Brothers in Arms, and
Mirror Dance)
5.
Memory
6.
Miles in Love omnibus (
Komarr,
A Civil Campaign and "Winterfair Gifts")
7.
Diplomatic Immunity
8.
Cryoburn
*Only available in the book
Dreamweaver's Dilemma, not published by Baen and to be honest not something I've been able to get a hold of. Not essential to any of the various stories in the other books so don't sweat if unavailable.
**The one Baen published book unavailable for that free download thing - and also one of the most pivotal in Miles Vorkosigan's character arc. This is a must read if you're reading the series and is well worth hunting down if you've got to this point.
***Although I put it at the start for consistency, really do not need to read either first if you're reading in in-universe order. I'd actually recommend reading
Falling Free at some time before "Labyrinth".
Anyway, hope this was helpful.