Dead Man's Cove by Lauren St John
The Case of the Ruby Necklace by Alex Carter
The Case of the Deadly Desperados by Caroline Lawrence
Mondays are Murder by Tanya Landman
The Mystery of the Whistling Caves by Helen Moss
and mentioned the sequels to those books. You can also read more about some of them in the Orion Star newsletter.
Another suggestion, that I haven't been able to get to in time is Small Change for Stuart by Lissa Evans:
As if being tiny and also having S.Horten as your name isn't bad enough, ten-year-old Stuart Horten is moved (by his very clever, but not very sensible parents) to Beeton, far away from all his friends. But in Beeton starts the strangest adventure of Stuart's life as he is swept up in a quest to find his uncle's old workshop - his famous magician, and also very short, uncle, that is...
The Book Zone has reviewed it and loved it!.
Then there are several series with links to Sherlock Holmes:
Author: Peter Abrahams
Series: Ingrid Levin-Hill (a big Sherlock Holmes fan), Echo Falls
1. Down the Rabbit Hole
2. Behind the Curtain
3. Into the Dark
Author: Andrew Lane
Series: Young Sherlock Holmes
1. The Death Cloud
2. Red Leech
3. Black Ice
Author: Tim Pigott-Smith
Series: The Baker Street Mysteries
1. The Dragon Tattoo
2. The Rose of Africa
3. The Shadow of Evil
Author: Anthony Read
Series: Baker Street Boys
1. The Case of the Disappearing Detective
2. The Case of the Captive Clairvoyant
3. The Case of the Ranjipur Ruby
4. The Case of the Limehouse Laundry
5. The Case of the Stolen Sparklers
6. The Case of the Haunted Horrors
And from my childhood:
"Carolyn Keene's" Nancy Drew continues to detect, most recently in the Sabotage Trilogy (2010/2011).
Franklin W Dixon's Hardy Boys are still strutting their stuff as the "Undercover Brothers", last seen in 2008's Feeding Frenzy.
My favourite series though, Alfred Hitchcock and the Three Investigators hasn't been picked up recently. I remember the excitement when I finally got hold of #1 in the series, The Secret of Terror Castle after I'd read so many of the later ones.