As you can see I am newbie ( my account too).
I am very interested to mine altcoins like eth but don't have any knowledge.
Here are my questions:-
My budget is $1k , which hardware I should buy. ( No problem of electricity)
If you're really that green, Id suggest starting with 2 GPUs on a motherboard with two PCIE16 slots. Once you get some experience you can decide if you want to add riser cards (1x -> 16x risers to allow you to put in more GPUs). For cards, take your pick, the type of card you buy will influence what coins are most profitable for you and how much you will make. Get a gold rated power supply of at least 750 watts if you want some room to add more cards. Don't skimp on a PS as they will contribute to your power usage.
Take a look at the profitability calculator on NiceHash.com for an idea of what GPUs are profitable at the moment. Unfortunately almost all of them are overpriced right now because of the current mining craze. Be careful to not overpay for GPUs as it will make it much harder to ROI.
Honestly, start doing some serious reading and watching youtube. If you can't build and support a home built PC then this is not the hobby for you.