The first half of April is Double VIP points at
LEGO. For those that don't know, a VIP member typically gets 5% back in points to spend toward a future purchase. 2X VIP points earns you 10%. It's a good time to buy Exclusive & Hard to Find sets.
Target on eBay has a great deal on the soon-to-disappear
Lone Ranger Constitution Train (79111).
At $73.99 (free shipping), it's been had at cheaper prices in previous clearance deals, but it's already retired from LEGO, so when it's gone, it's gone.
Target on eBay also has the
City Forest Police Station (4440) for $54.99. Again, this one's also gone from LEGO directly, so if you want this one, now might be the time.
Amazon always has dozens of sets on sale, but a couple stand out with Super Heroes being my favorite theme so far.
LEGO Super Heroes Iron Man Malibu Mansion Attack (76007) $29.49
LEGO Superheroes 76011 Batman: Man-Bat Attack $16.00
If you notice on Amazon, retired
Super Heroes sets jump up quickly, so getting
Malibu Mansion at 25% off is good any time. The
Man-Bat set is quite new, so it'll be on shelves longer than
Malibu, but it's nice to get a new set marked down so early.