I will use your referral link if you help me to get an answer on this questions:

To make max profit i need to buy WTT tokens + miners right?
-- Maximum profit you do need WTT tokens + the miner, and you do get first dibs on the mining space; as opposed to those without the tokens (who only have a miner) but you do not necessarily need the tokens to be able to mine with giga-watt.
I will start mining only when miners will be delivered or it is like immediate cloud mining?
-- I believe the miners that are sold out are miners they already had in stock, and ready to use such as the btc miner and the panda miner for eth.  They sold out because they were ready to go right at that moment, essentially immediate cloud mining.   In the case of the ltc miner with it arriving on September 30th, you would have to wait unfortunately before mining.
How much WTT i need to buy for 1 L3+ miner?
-- 880 WTT tokens, calculation is done as follows for other mining units they offer:
  Power consumption + % listed underneath power consumption = how many WTT tokens you will need per miner
By buying WTT tokens i make profit only when price will go up (If i sell it) or i will also have some other income from it?
-- If you choose to trade them immediately, you would only make profit when they go up in value.
    If you choose to mine with the tokens/miner combination their value is a cost savings benefit to your mining efforts.
   If you choose to rent your tokens, you will earn money at your specified rental rate; only when the tokens are rented by another miner.
   In my mind the best way to utilize the tokens is as a semi long term investment, mining coins until the miner efficiency is no longer profitable and then either renting the tokens out to other miners or selling them.  At that point it will be quite a challenge deciding because in theory if 2 years is the end of a miner, I still have 48 years of rental capability and passive income.

How i understand it will be more profitable to order miner from shop.bitmain and send it to their address (Giga Watt) to be able mining other coins then LTC?
-- In some cases it may be more profitable ordering the miners yourself and shipping it to them however you have to pay an additional $20 hosting fee which may or may not diminish returns, and would also require shipping costs. 
(I've personally only contacted them about personally ordering pandaminers from pandaminer to ship to them)
My email with their customer support said they are working to offer the ability to mine XMR, ZEC and ETC; but for the time being only offer BTC, LTC and ETH mining.