Modern computers can seed RNGs based on shot noise, or quantum mirrors. Both of these methods produce truly random seeding for a shuffling algorithm. Now this doesn't mean that all poker sites that are claiming to use such a method are using such a method, or that cheating has never occurred in the online poker industry, but to say that it is impossible for a computer to create a random deck of cards is nonsense, because randomness is required for the field of cryptography, and as such random number generation has been highly researched by computer scientists. To be perfectly frank, modern RNGs can be more random than a live person shuffling cards, as a RNG is not biased by the previous position of cards in the deck like a live shuffle is. (This is how shuffle tracking works in blackjack)
There are many reasons why online poker is harder to win at than live poker, and it's not because it's like playing a PS3 game. Well maybe it is, but not what you think. Online is harder because most skilled players are playing multiple tables at a time to increase their earnings and decrease variance. Imagine if at your live cardroom you had one or two highly talented players that you could never beat. You try to avoid playing at tables with them, or get position on them when you do, because it's so hard to beat them. Now imagine if they are now playing 12, 16 or even 24 tables at once! Hard to avoid them now, isn't it? All the while, the people who are losing the money are only playing one, or maybe 2 tables. Hard to find them now isn't it? THAT is why you're having a hard time winning at poker now. And all those guys at your casino, the ones who can barely keep the drool off their cards as they limp call all in with their 68 offsuit? They all think playing online is illegal (if they live in the US), or that it's "rigged", and won't play. One less guy you have losing money at the table. And Poker's a 0 sum game-For you to be winning, someone has got to be losing. And since the house is raking, no matter what, someone is losing!
And good luck with that whole "know I'm not getting screwed for sure" thing. Bodog has a reputation for dealing dual lines. This is illegal in Vegas and frowned upon everywhere else. Here's an example of what I mean. Bodog has a decent number of customers, who, for example, will just bet on the Lakers to win no matter what. So if Vegas sets the line for the Lakers game at -6 in their favor, most online books will match that to start. Bodog will identify their customers who only bet on the Lakers, and offer them a worse like, say -6.5 or -7, when every other book, and their other customers, will see the standard -6. So if you bet like that, Bodog will ABSOLUTELY screw you. Unlike pokersites, where as long as everything is on the up and up, you'll just have to deal with better players, coolers, and all the variance that comes with seeing thousands of hands at a time. There have been times where not everything has been on the up and up. Cereus and Pitbull poker have proven this. But to say that the entire idea of online poker is impossible to be on the up and up because you think that computers cannot generate a random deck of cards is simply absurd.