AMC, the creators of Breaking Bad, released the first five webisodes in the build up to Season 2. They were eventually released on the Season 2 boxset.
So you can watch Specials 1 - 5 as soon as you finish Season 1.
As for the rest of your list, I suspect the episode 7 gap is simply an oversight (and one that has been copied by other sites, e.g. here). The best source for this information would be AMC themselves. They list the episodes here, in no obvious order.
Users online have attempted to state their correct order. This user on TheTVDB.com stated the order was:
01 - Better Call Saul - Carl B.
02 - Better Call Saul - Saul Better
Help My Mom
03 - Better Call Saul - Badger
04 - Better Call Saul -
05 - Better Call Saul - Wayfarer 515
06 - Team
07 - Better Call Saul - Wendy
08 - Better Call Saul -
Who Can You Sue
09 - Letters to Saul - Did I Murder an Old Man
Live Saul Cam
IMDB on the other hand have a totally different order listed (along with different episode titles!). Despite this, the order pasted above appears to be the most consistently quoted order (matching the one you posted).
I did come across quite a few torrent sites online with the series listed and the episodes all listed in the order pasted above as part of the Season 3 extras (that is, released after Season 2 and before Season 3). This would suit the timeline listed for them (2010).
Therefore, I would conclude this:
- There is no episode 7. That's simply a mistake that has been copied in quite a few places. Or rather, there is an episode 7, but the gap suggesting there isn't is a mistake.
- Watch Specials 1 - 5 after Season 1.
- Watch Specials in order pasted above after Season 2.
- Watch Season 4 Sneak Peek after Season 3.
- I'm not sure why these episodes aren't more recognised (I didn't even know they existed until this question). It seems particularly strange given that Better Call Saul is now in confirmed production.